diff --git a/packages/common/http/src/params.ts b/packages/common/http/src/params.ts
index 87cdedd61c..b4841570c8 100644
--- a/packages/common/http/src/params.ts
+++ b/packages/common/http/src/params.ts
@@ -73,7 +73,10 @@ export class HttpUrlEncodingCodec implements HttpParameterCodec {
 function paramParser(rawParams: string, codec: HttpParameterCodec): Map<string, string[]> {
   const map = new Map<string, string[]>();
   if (rawParams.length > 0) {
-    const params: string[] = rawParams.split('&');
+    // The `window.location.search` can be used while creating an instance of the `HttpParams` class
+    // (e.g. `new HttpParams({ fromString: window.location.search })`). The `window.location.search`
+    // may start with the `?` char, so we strip it if it's present.
+    const params: string[] = rawParams.replace(/^\?/, '').split('&');
     params.forEach((param: string) => {
       const eqIdx = param.indexOf('=');
       const [key, val]: string[] = eqIdx == -1 ?
diff --git a/packages/common/http/test/params_spec.ts b/packages/common/http/test/params_spec.ts
index 9cd8422624..60d20421a0 100644
--- a/packages/common/http/test/params_spec.ts
+++ b/packages/common/http/test/params_spec.ts
@@ -21,6 +21,19 @@ import {HttpParams} from '@angular/common/http/src/params';
         expect(body.getAll('a')).toEqual(['b']);
         expect(body.getAll('c')).toEqual(['d', 'e']);
       });
+
+      it('should ignore question mark in a url', () => {
+        const body = new HttpParams({fromString: '?a=b&c=d&c=e'});
+        expect(body.getAll('a')).toEqual(['b']);
+        expect(body.getAll('c')).toEqual(['d', 'e']);
+      });
+
+      it('should only remove question mark at the beginning of the params', () => {
+        const body = new HttpParams({fromString: '?a=b&c=d&?e=f'});
+        expect(body.getAll('a')).toEqual(['b']);
+        expect(body.getAll('c')).toEqual(['d']);
+        expect(body.getAll('?e')).toEqual(['f']);
+      });
     });
 
     describe('lazy mutation', () => {