diff --git a/packages/service-worker/worker/main.ts b/packages/service-worker/worker/main.ts
index 11f86ccb5e..dab1ec368e 100644
--- a/packages/service-worker/worker/main.ts
+++ b/packages/service-worker/worker/main.ts
@@ -12,5 +12,5 @@ import {Driver} from './src/driver';
 
 const scope = self as any as ServiceWorkerGlobalScope;
 
-const adapter = new Adapter();
+const adapter = new Adapter(scope);
 const driver = new Driver(scope, adapter, new CacheDatabase(scope, adapter));
diff --git a/packages/service-worker/worker/src/adapter.ts b/packages/service-worker/worker/src/adapter.ts
index 2e2847d62e..5955cdd56b 100644
--- a/packages/service-worker/worker/src/adapter.ts
+++ b/packages/service-worker/worker/src/adapter.ts
@@ -13,6 +13,15 @@
  * from the global scope.
  */
 export class Adapter {
+  readonly cacheNamePrefix: string;
+
+  constructor(scope: ServiceWorkerGlobalScope) {
+    // Suffixing `ngsw` with the baseHref to avoid clash of cache names
+    // for SWs with different scopes on the same domain.
+    const baseHref = new URL(scope.registration.scope).pathname;
+    this.cacheNamePrefix = 'ngsw:' + baseHref;
+  }
+
   /**
    * Wrapper around the `Request` constructor.
    */
diff --git a/packages/service-worker/worker/src/app-version.ts b/packages/service-worker/worker/src/app-version.ts
index dafdcabfe0..5db2d6d3a4 100644
--- a/packages/service-worker/worker/src/app-version.ts
+++ b/packages/service-worker/worker/src/app-version.ts
@@ -72,7 +72,7 @@ export class AppVersion implements UpdateSource {
     this.assetGroups = (manifest.assetGroups || []).map(config => {
       // Every asset group has a cache that's prefixed by the manifest hash and the name of the
       // group.
-      const prefix = `ngsw:${this.manifestHash}:assets`;
+      const prefix = `${adapter.cacheNamePrefix}:${this.manifestHash}:assets`;
       // Check the caching mode, which determines when resources will be fetched/updated.
       switch (config.installMode) {
         case 'prefetch':
@@ -89,7 +89,7 @@ export class AppVersion implements UpdateSource {
                           .map(
                               config => new DataGroup(
                                   this.scope, this.adapter, config, this.database,
-                                  `ngsw:${config.version}:data`));
+                                  `${adapter.cacheNamePrefix}:${config.version}:data`));
 
     // This keeps backwards compatibility with app versions without navigation urls.
     // Fix: https://github.com/angular/angular/issues/27209
diff --git a/packages/service-worker/worker/src/db-cache.ts b/packages/service-worker/worker/src/db-cache.ts
index 581aadf2fb..2a4b112821 100644
--- a/packages/service-worker/worker/src/db-cache.ts
+++ b/packages/service-worker/worker/src/db-cache.ts
@@ -23,16 +23,17 @@ export class CacheDatabase implements Database {
     if (this.tables.has(name)) {
       this.tables.delete(name);
     }
-    return this.scope.caches.delete(`ngsw:db:${name}`);
+    return this.scope.caches.delete(`${this.adapter.cacheNamePrefix}:db:${name}`);
   }
 
   list(): Promise<string[]> {
-    return this.scope.caches.keys().then(keys => keys.filter(key => key.startsWith('ngsw:db:')));
+    return this.scope.caches.keys().then(
+        keys => keys.filter(key => key.startsWith(`${this.adapter.cacheNamePrefix}:db:`)));
   }
 
   open(name: string): Promise<Table> {
     if (!this.tables.has(name)) {
-      const table = this.scope.caches.open(`ngsw:db:${name}`)
+      const table = this.scope.caches.open(`${this.adapter.cacheNamePrefix}:db:${name}`)
                         .then(cache => new CacheTable(name, cache, this.adapter));
       this.tables.set(name, table);
     }
diff --git a/packages/service-worker/worker/src/driver.ts b/packages/service-worker/worker/src/driver.ts
index 186f21ed80..d7b69ba57f 100644
--- a/packages/service-worker/worker/src/driver.ts
+++ b/packages/service-worker/worker/src/driver.ts
@@ -705,7 +705,7 @@ export class Driver implements Debuggable, UpdateSource {
 
   private async deleteAllCaches(): Promise<void> {
     await(await this.scope.caches.keys())
-        .filter(key => key.startsWith('ngsw:'))
+        .filter(key => key.startsWith(`${this.adapter.cacheNamePrefix}:`))
         .reduce(async(previous, key) => {
           await Promise.all([
             previous,
@@ -924,9 +924,7 @@ export class Driver implements Debuggable, UpdateSource {
    */
   async cleanupOldSwCaches(): Promise<void> {
     const cacheNames = await this.scope.caches.keys();
-    const oldSwCacheNames =
-        cacheNames.filter(name => /^ngsw:(?:active|staged|manifest:.+)$/.test(name));
-
+    const oldSwCacheNames = cacheNames.filter(name => /^ngsw:(?!\/)/.test(name));
     await Promise.all(oldSwCacheNames.map(name => this.scope.caches.delete(name)));
   }
 
diff --git a/packages/service-worker/worker/test/happy_spec.ts b/packages/service-worker/worker/test/happy_spec.ts
index 59ce6d6d1f..95bf43eec3 100644
--- a/packages/service-worker/worker/test/happy_spec.ts
+++ b/packages/service-worker/worker/test/happy_spec.ts
@@ -587,7 +587,7 @@ import {async_beforeEach, async_fit, async_it} from './async';
       serverUpdate.assertNoOtherRequests();
 
       let keys = await scope.caches.keys();
-      let hasOriginalCaches = keys.some(name => name.startsWith(`ngsw:${manifestHash}:`));
+      let hasOriginalCaches = keys.some(name => name.startsWith(`ngsw:/:${manifestHash}:`));
       expect(hasOriginalCaches).toEqual(true);
 
       scope.clients.remove('default');
@@ -600,7 +600,7 @@ import {async_beforeEach, async_fit, async_it} from './async';
       expect(await makeRequest(scope, '/foo.txt')).toEqual('this is foo v2');
 
       keys = await scope.caches.keys();
-      hasOriginalCaches = keys.some(name => name.startsWith(`ngsw:${manifestHash}:`));
+      hasOriginalCaches = keys.some(name => name.startsWith(`ngsw:/:${manifestHash}:`));
       expect(hasOriginalCaches).toEqual(false);
     });
 
@@ -938,13 +938,21 @@ import {async_beforeEach, async_fit, async_it} from './async';
 
     describe('cleanupOldSwCaches()', () => {
       async_it('should delete the correct caches', async() => {
-        const oldSwCacheNames = ['ngsw:active', 'ngsw:staged', 'ngsw:manifest:a1b2c3:super:duper'];
+        const oldSwCacheNames = [
+          // Example cache names from the beta versions of `@angular/service-worker`.
+          'ngsw:active',
+          'ngsw:staged',
+          'ngsw:manifest:a1b2c3:super:duper',
+          // Example cache names from the beta versions of `@angular/service-worker`.
+          'ngsw:a1b2c3:assets:foo',
+          'ngsw:db:a1b2c3:assets:bar',
+        ];
         const otherCacheNames = [
           'ngsuu:active',
           'not:ngsw:active',
-          'ngsw:staged:not',
           'NgSw:StAgEd',
-          'ngsw:manifest',
+          'ngsw:/:active',
+          'ngsw:/foo/:staged',
         ];
         const allCacheNames = oldSwCacheNames.concat(otherCacheNames);
 
diff --git a/packages/service-worker/worker/testing/scope.ts b/packages/service-worker/worker/testing/scope.ts
index f2c0d1f66e..1ce31cde4b 100644
--- a/packages/service-worker/worker/testing/scope.ts
+++ b/packages/service-worker/worker/testing/scope.ts
@@ -74,6 +74,7 @@ export class MockClients implements Clients {
 }
 
 export class SwTestHarness implements ServiceWorkerGlobalScope, Adapter, Context {
+  readonly cacheNamePrefix: string;
   readonly clients = new MockClients();
   private eventHandlers = new Map<string, Function>();
   private skippedWaiting = true;
@@ -115,6 +116,8 @@ export class SwTestHarness implements ServiceWorkerGlobalScope, Adapter, Context
 
   constructor(private server: MockServerState, readonly caches: MockCacheStorage) {
     this.time = Date.now();
+    const baseHref = new URL(this.registration.scope).pathname;
+    this.cacheNamePrefix = 'ngsw:' + baseHref;
   }
 
   async resolveSelfMessages(): Promise<void> {