Google Inc. is in talks with several makers of popular online games as it seeks to develop a broader social-networking service that could compete with Facebook Inc., according to people familiar with the matter.

Google has been in discussions with top developers to offer their games on a new service it is building, these people said. Those developers include Playdom Inc., Electronic Arts Inc.'s Playfish and Zynga Game Network Inc.—a company in which Google recently took a financial stake, these people said.

It...