This study investigated the level and frequency of science teachers' use of computer applications as an instructional tool in the classroom. The manner and frequency of science teachers' use of computer, their perceptions about integration of computer applications, and other factors contributed to changes in their computer literacy are investigated in this study. 63 primary school science teachers from the Northwestern part of Turkey participated in this study. A survey was administered to teachers. Results demonstrated that improving the computer literacy of science teachers seems to increase science teachers' computer use and consequently increase their integration of computer applications as an instructional tool. Internet, email, and educational software CDs found to have high percentage in teachers' use of computer applications in the classrooms. Also, the results indicated gender difference exists between science teachers' integration of computer applications as an instructional tool.