The study investigated the thinking game theory by Malone ¡]1981¡^ and game design program by Fang, Sheng-Wen¡]1994¡^ , to develop design structure for computer instructional games and expect that has any help in the future. In compliance with this structure to design computer instructional game, further explored (1)the related with the background and learning interests; (2)the influence of the game vision¡Binterest drama and learning interests¡Blearning effectiveness; (3)the related with using computer degree and city; (4)the influence of similarities of using computer degree and learning interests, effectiveness; (5)Is there any related with learning effectiveness and leaning instruction content or not? (6)There has what kind of learning effectiveness in using computer instructional game. The instructional computer game is to assist community subject¡¦s first unit at fifth grade in primary school, total of 124 participants (include 5th and 4th grade students). Analyzed with Chi-square test, Mc-Nemar test, Gamma coefficient and G2 test. The study found from statistical analysis that (1) Instructional computer game can increase learning interests, no matter what students¡¦ background are; (2) Fun script and good screen design can increase learning interests, but can¡¦t get learning effectiveness higher; (3)The students who didn¡¦t like social study, indeed have higher learning interests after using this instructional computer game; (4)Students who like instructional computer game or not, will effect learning effectiveness; (5)The degree of using computer between city and county is about the same; (6)Learning effectiveness for memory questions is increased after play this instructional compuetr game; (7)Students who had learned the subject matter efore or not, would effect learning effectiveness.