Although motivation and fun are important for effective speech therapy, the conventional speech therapy is often conducted by using a textbook which can be boring to the speech-handicapped. The present study is to develop a speech therapy serious game for rehabilitation of the handicapped with articulation and fluency in speech. A speech therapy game was developed in the present study through the following four-step approach: (1) benchmarking analysis of 8 speech therapy systems, (2) analysis of 22 parents, (3) development of the framework of the speech therapy game and ideas for speech therapy game contents, and (4) implementation of the speech therapy serious game system using C# and the game engine Unity. The speech therapy serous game developed in the study can be of help for rehabilitation of articulation and fluency for the speech-handicapped.