diff --git a/types/jasmine/index.d.ts b/types/jasmine/index.d.ts
index b10db4645e..1a59399c1a 100644
--- a/types/jasmine/index.d.ts
+++ b/types/jasmine/index.d.ts
@@ -9,6 +9,7 @@
 //                 Chris Yungmann <https://github.com/cyungmann>
 //                 Giles Roadnight <https://github.com/Roaders>
 //                 Yaroslav Admin <https://github.com/devoto13>
+//                 Domas Trijonis <https://github.com/fdim>
 // Definitions: https://github.com/DefinitelyTyped/DefinitelyTyped
 // TypeScript Version: 2.8
 // For ddescribe / iit use : https://github.com/DefinitelyTyped/DefinitelyTyped/blob/master/karma-jasmine/karma-jasmine.d.ts
@@ -643,8 +644,8 @@ declare namespace jasmine {
         withArgs(...args: any[]): Spy;
     }
 
-    type SpyObj<T> = T & {
-      [k in keyof T]: Spy;
+    type SpyObj<T> = {
+        [k in keyof T]: T[k] extends Function ? T[k] & Spy : T[k];
     }
 
     interface SpyAnd {
diff --git a/types/jasmine/jasmine-tests.ts b/types/jasmine/jasmine-tests.ts
index 31bdd5f46c..e4208b0b50 100644
--- a/types/jasmine/jasmine-tests.ts
+++ b/types/jasmine/jasmine-tests.ts
@@ -701,11 +701,20 @@ describe("A spy, when created manually", () => {
 });
 
 describe("Multiple spies, when created manually", () => {
-    var tape: any;
+    interface Tape {
+        play(): void;
+        pause(): void;
+        rewind(pos: number): void;
+        stop(): void;
+        readonly isPlaying: boolean; // spy obj makes this writable
+    }
+
+    var tape: jasmine.SpyObj<Tape>;
     var el: jasmine.SpyObj<Element>;
 
     beforeEach(() => {
-        tape = jasmine.createSpyObj('tape', ['play', 'pause', 'stop', 'rewind']);
+        tape = jasmine.createSpyObj<Tape>('tape', ['play', 'pause', 'stop', 'rewind']);
+        (tape as { isPlaying: boolean }).isPlaying = false;
         el = jasmine.createSpyObj<Element>('Element', ['hasAttribute']);
 
         el.hasAttribute.and.returnValue(false);
@@ -733,6 +742,10 @@ describe("Multiple spies, when created manually", () => {
     it("tracks all the arguments of its calls", () => {
         expect(tape.rewind).toHaveBeenCalledWith(0);
     });
+
+    it("read isPlaying property", () => {
+        expect(tape.isPlaying).toBe(false);
+    })
 });
 
 describe("jasmine.nothing", () => {
diff --git a/types/jasmine/v2/index.d.ts b/types/jasmine/v2/index.d.ts
index 4a15b3d1da..4211cf2ca0 100644
--- a/types/jasmine/v2/index.d.ts
+++ b/types/jasmine/v2/index.d.ts
@@ -8,6 +8,7 @@
 //                 Boris Breuer <https://github.com/Engineer2B>
 //                 Chris Yungmann <https://github.com/cyungmann>
 //                 Yaroslav Admin <https://github.com/devoto13>
+//                 Domas Trijonis <https://github.com/fdim>
 // Definitions: https://github.com/DefinitelyTyped/DefinitelyTyped
 // TypeScript Version: 2.8
 // For ddescribe / iit use : https://github.com/DefinitelyTyped/DefinitelyTyped/blob/master/karma-jasmine/karma-jasmine.d.ts
@@ -628,8 +629,8 @@ declare namespace jasmine {
         calls: Calls;
     }
 
-    type SpyObj<T> = T & {
-      [k in keyof T]: Spy;
+    type SpyObj<T> = {
+        [k in keyof T]: T[k] extends Function ? T[k] & Spy : T[k];
     }
 
     interface SpyAnd {
diff --git a/types/jasmine/v2/jasmine-tests.ts b/types/jasmine/v2/jasmine-tests.ts
index fce7c59c9e..7ac8339a3e 100644
--- a/types/jasmine/v2/jasmine-tests.ts
+++ b/types/jasmine/v2/jasmine-tests.ts
@@ -643,11 +643,20 @@ describe("A spy, when created manually", () => {
 });
 
 describe("Multiple spies, when created manually", () => {
-    var tape: any;
+    interface Tape {
+        play(): void;
+        pause(): void;
+        rewind(pos: number): void;
+        stop(): void;
+        readonly isPlaying: boolean; // spy obj makes this writable
+    }
+
+    var tape: jasmine.SpyObj<Tape>;
     var el: jasmine.SpyObj<Element>;
 
     beforeEach(() => {
-        tape = jasmine.createSpyObj('tape', ['play', 'pause', 'stop', 'rewind']);
+        tape = jasmine.createSpyObj<Tape>('tape', ['play', 'pause', 'stop', 'rewind']);
+        (tape as { isPlaying: boolean }).isPlaying = false;
         el = jasmine.createSpyObj<Element>('Element', ['hasAttribute']);
 
         el.hasAttribute.and.returnValue(false);
@@ -675,6 +684,10 @@ describe("Multiple spies, when created manually", () => {
     it("tracks all the arguments of its calls", () => {
         expect(tape.rewind).toHaveBeenCalledWith(0);
     });
+
+    it("read isPlaying property", () => {
+        expect(tape.isPlaying).toBe(false);
+    })
 });
 
 describe("jasmine.nothing", () => {