The aim of this study was to examine the effect of teaching Physics through project method on academic achievement of secondary schools students in the subject of Physics. In this study, an achievement test (pre-test/post-test) covering eight chapters were used as measuring instrument. Depending upon pre academic achievement test scores, eighty (80) science students of 10th class were divided into two equal groups named as experimental group and control group. The experimental group was taught through project method and the control group was taught by traditional lecture method. Both the groups were taught for a period of six weeks (40 minutes period per day). The Post test was administered at end of treatments. The marks obtain in Pretest and Posttest of both groups served as data of this study.The analysis of data revealed that on whole, experimental group showed better performance than controlled group. Furthermore the experimental group performed significantly better than control group in learning domain (knowledge, comprehension, and application and skill developments). The results this study indicated that teaching Physics through Project method was more effective as compared to traditional lecture method at secondary level. Keywords: Physics teaching, Project method, traditional teaching lecture method and academic achievements