Cooperative learning with group investigation (GI) is one of the learning methods involving more students to actively participate in learning process. This research is aimed to (1) enhance the learning quality through the implementation of innovative learning strategy; and (2) see the effectiveness of using cooperative learning strategy in enhancing learning quality of biology. Type of this research is action research conducted to the eleventh grader of natural science on the public senior high school no.91 Jakarta from February to April 2009. The techniques of data collections used are (a) observation on the students activeness during the class, (b) interview on the students, and (c) formative test when each cycle ends. The procedures of the research include; (a) planning,(b) acting, (c) observing, (d) reflecting. The results show that there is significantly an increasing score of biology learning achievement by cooperative learning with GI model compared to the previous learning strategy.