diff --git a/packages/compiler-cli/ngcc/src/packages/entry_point_bundle.ts b/packages/compiler-cli/ngcc/src/packages/entry_point_bundle.ts
index d61f12341b..166873090e 100644
--- a/packages/compiler-cli/ngcc/src/packages/entry_point_bundle.ts
+++ b/packages/compiler-cli/ngcc/src/packages/entry_point_bundle.ts
@@ -12,7 +12,7 @@ import {FileSystem} from '../file_system/file_system';
 import {PathMappings} from '../utils';
 import {BundleProgram, makeBundleProgram} from './bundle_program';
 import {EntryPointFormat, EntryPointJsonProperty} from './entry_point';
-import {NgccCompilerHost} from './ngcc_compiler_host';
+import {NgccCompilerHost, NgccSourcesCompilerHost} from './ngcc_compiler_host';
 
 /**
  * A bundle of files and paths (and TS programs) that correspond to a particular
@@ -48,16 +48,17 @@ export function makeEntryPointBundle(
     noLib: true,
     rootDir: entryPointPath, ...pathMappings
   };
-  const host = new NgccCompilerHost(fs, options);
+  const srcHost = new NgccSourcesCompilerHost(fs, options, entryPointPath);
+  const dtsHost = new NgccCompilerHost(fs, options);
   const rootDirs = [AbsoluteFsPath.from(entryPointPath)];
 
   // Create the bundle programs, as necessary.
   const src = makeBundleProgram(
       fs, isCore, AbsoluteFsPath.resolve(entryPointPath, formatPath), 'r3_symbols.js', options,
-      host);
+      srcHost);
   const dts = transformDts ? makeBundleProgram(
                                  fs, isCore, AbsoluteFsPath.resolve(entryPointPath, typingsPath),
-                                 'r3_symbols.d.ts', options, host) :
+                                 'r3_symbols.d.ts', options, dtsHost) :
                              null;
   const isFlatCore = isCore && src.r3SymbolsFile === null;
 
diff --git a/packages/compiler-cli/ngcc/src/packages/ngcc_compiler_host.ts b/packages/compiler-cli/ngcc/src/packages/ngcc_compiler_host.ts
index 8f8d5cd597..19ddb626dd 100644
--- a/packages/compiler-cli/ngcc/src/packages/ngcc_compiler_host.ts
+++ b/packages/compiler-cli/ngcc/src/packages/ngcc_compiler_host.ts
@@ -10,11 +10,12 @@ import * as ts from 'typescript';
 
 import {AbsoluteFsPath} from '../../../src/ngtsc/path';
 import {FileSystem} from '../file_system/file_system';
+import {isRelativePath} from '../utils';
 
 export class NgccCompilerHost implements ts.CompilerHost {
   private _caseSensitive = this.fs.exists(AbsoluteFsPath.fromUnchecked(__filename.toUpperCase()));
 
-  constructor(private fs: FileSystem, private options: ts.CompilerOptions) {}
+  constructor(protected fs: FileSystem, protected options: ts.CompilerOptions) {}
 
   getSourceFile(fileName: string, languageVersion: ts.ScriptTarget): ts.SourceFile|undefined {
     const text = this.readFile(fileName);
@@ -64,3 +65,41 @@ export class NgccCompilerHost implements ts.CompilerHost {
     return this.fs.readFile(AbsoluteFsPath.fromUnchecked(fileName));
   }
 }
+
+/**
+ * Represents a compiler host that resolves a module import as a JavaScript source file if
+ * available, instead of the .d.ts typings file that would have been resolved by TypeScript. This
+ * is necessary for packages that have their typings in the same directory as the sources, which
+ * would otherwise let TypeScript prefer the .d.ts file instead of the JavaScript source file.
+ */
+export class NgccSourcesCompilerHost extends NgccCompilerHost {
+  private cache = ts.createModuleResolutionCache(
+      this.getCurrentDirectory(), file => this.getCanonicalFileName(file));
+
+  constructor(fs: FileSystem, options: ts.CompilerOptions, protected entryPointPath: string) {
+    super(fs, options);
+  }
+
+  resolveModuleNames(
+      moduleNames: string[], containingFile: string, reusedNames?: string[],
+      redirectedReference?: ts.ResolvedProjectReference): Array<ts.ResolvedModule|undefined> {
+    return moduleNames.map(moduleName => {
+      const {resolvedModule} = ts.resolveModuleName(
+          moduleName, containingFile, this.options, this, this.cache, redirectedReference);
+
+      // If the module request originated from a relative import in a JavaScript source file,
+      // TypeScript may have resolved the module to its .d.ts declaration file if the .js source
+      // file was in the same directory. This is undesirable, as we need to have the actual
+      // JavaScript being present in the program. This logic recognizes this scenario and rewrites
+      // the resolved .d.ts declaration file to its .js counterpart, if it exists.
+      if (resolvedModule !== undefined && resolvedModule.extension === ts.Extension.Dts &&
+          containingFile.endsWith('.js') && isRelativePath(moduleName)) {
+        const jsFile = resolvedModule.resolvedFileName.replace(/\.d\.ts$/, '.js');
+        if (this.fileExists(jsFile)) {
+          return {...resolvedModule, resolvedFileName: jsFile, extension: ts.Extension.Js};
+        }
+      }
+      return resolvedModule;
+    });
+  }
+}
diff --git a/packages/compiler-cli/ngcc/test/packages/entry_point_bundle_spec.ts b/packages/compiler-cli/ngcc/test/packages/entry_point_bundle_spec.ts
new file mode 100644
index 0000000000..b976f9487a
--- /dev/null
+++ b/packages/compiler-cli/ngcc/test/packages/entry_point_bundle_spec.ts
@@ -0,0 +1,120 @@
+/**
+ * @license
+ * Copyright Google Inc. All Rights Reserved.
+ *
+ * Use of this source code is governed by an MIT-style license that can be
+ * found in the LICENSE file at https://angular.io/license
+ */
+
+import {makeEntryPointBundle} from '../../src/packages/entry_point_bundle';
+import {MockFileSystem} from '../helpers/mock_file_system';
+
+function createMockFileSystem() {
+  return new MockFileSystem({
+    '/node_modules/test': {
+      'package.json':
+          '{"module": "./index.js", "es2015": "./es2015/index.js", "typings": "./index.d.ts"}',
+      'index.d.ts': 'export * from "./public_api";',
+      'index.js': 'export * from "./public_api";',
+      'index.metadata.json': '...',
+      'public_api.d.ts': `
+        export * from "test/secondary";
+        export * from "./nested";
+        export declare class TestClass {};
+      `,
+      'public_api.js': `
+        export * from "test/secondary";
+        export * from "./nested";
+        export const TestClass = function() {};
+       `,
+      'root.d.ts': `
+        import * from 'other';
+        export declare class RootClass {};
+      `,
+      'root.js': `
+        import * from 'other';
+        export const RootClass = function() {};
+      `,
+      'nested': {
+        'index.d.ts': 'export * from "../root";',
+        'index.js': 'export * from "../root";',
+      },
+      'es2015': {
+        'index.js': 'export * from "./public_api";',
+        'public_api.js': 'export class TestClass {};',
+        'root.js': `
+          import * from 'other';
+          export class RootClass {};
+        `,
+        'nested': {
+          'index.js': 'export * from "../root";',
+        },
+      },
+      'secondary': {
+        'package.json':
+            '{"module": "./index.js", "es2015": "./es2015/index.js", "typings": "./index.d.ts"}',
+        'index.d.ts': 'export * from "./public_api";',
+        'index.js': 'export * from "./public_api";',
+        'index.metadata.json': '...',
+        'public_api.d.ts': 'export declare class SecondaryClass {};',
+        'public_api.js': 'export class SecondaryClass {};',
+        'es2015': {
+          'index.js': 'export * from "./public_api";',
+          'public_api.js': 'export class SecondaryClass {};',
+        },
+      },
+    },
+    '/node_modules/other': {
+      'package.json':
+          '{"module": "./index.js", "es2015": "./es2015/index.js", "typings": "./index.d.ts"}',
+      'index.d.ts': 'export * from "./public_api";',
+      'index.js': 'export * from "./public_api";',
+      'index.metadata.json': '...',
+      'public_api.d.ts': 'export declare class OtherClass {};',
+      'public_api.js': 'export class OtherClass {};',
+      'es2015': {
+        'index.js': 'export * from "./public_api";',
+        'public_api.js': 'export class OtherClass {};',
+      },
+    },
+  });
+}
+
+describe('entry point bundle', () => {
+  // https://github.com/angular/angular/issues/29939
+  it('should resolve JavaScript sources instead of declaration files if they are adjacent', () => {
+    const fs = createMockFileSystem();
+    const esm5bundle = makeEntryPointBundle(
+        fs, '/node_modules/test', './index.js', './index.d.ts', false, 'esm5', 'esm5', true) !;
+
+    expect(esm5bundle.src.program.getSourceFiles().map(sf => sf.fileName))
+        .toEqual(jasmine.arrayWithExactContents([
+          // Modules from the entry-point itself should be source files
+          '/node_modules/test/index.js',
+          '/node_modules/test/public_api.js',
+          '/node_modules/test/nested/index.js',
+          '/node_modules/test/root.js',
+
+          // Modules from a secondary entry-point should be declaration files
+          '/node_modules/test/secondary/public_api.d.ts',
+          '/node_modules/test/secondary/index.d.ts',
+
+          // Modules resolved from "other" should be declaration files
+          '/node_modules/other/public_api.d.ts',
+          '/node_modules/other/index.d.ts',
+        ]));
+
+    expect(esm5bundle.dts !.program.getSourceFiles().map(sf => sf.fileName))
+        .toEqual(jasmine.arrayWithExactContents([
+          // All modules in the dts program should be declaration files
+          '/node_modules/test/index.d.ts',
+          '/node_modules/test/public_api.d.ts',
+          '/node_modules/test/nested/index.d.ts',
+          '/node_modules/test/root.d.ts',
+          '/node_modules/test/secondary/public_api.d.ts',
+          '/node_modules/test/secondary/index.d.ts',
+          '/node_modules/other/public_api.d.ts',
+          '/node_modules/other/index.d.ts',
+        ]));
+  });
+});