In this study, it has been aimed to determine the effect of project based learning approach applied at 7th grade Science and Technology Lesson of Elementary School to motivation levels of students against this lesson. This study has been executed by total 75 students of 7th grade in an Elementary School. 39 of these students has formed the experimental group and 36 of them has formed the control group. For the experimental group, project based learning approach has been used and for the control group, traditional learning approach has been applied. At the study, Motivated Strategies for Learning Questionnaire has been used to collect data. At the end of the study, a statistically meaningful difference on behalf of motivation levels of experimental group students over whom project based learning approach has been applied, has been observed for science and technology when compared by motivation levels of control group students over whom traditional learning approach has been applied. Besides, after the application, there has been a statistically meaningful difference on behalf of experimental group; at linear direction when regarding self organization, cognitive strategy usage, self - sufficiency, intrinsic value sub dimensions of motivation and at adverse direction when regarding exam stress sub dimension.