This study aims at determining the factors influencing the 15 year olds' success at science in Turkey within the framework of the Programme for International Students' Achievement (PISA). The research has been conducted with 4942 students aged 15. In the analysis of the data, questions on the students' questionaire were specified through fundamental components paraphrasing factors analysis so as to determine the factors affecting success at science. Procedural multi-regression analysis was used in determining the predicting power of the predictive variables concerning the 15 year olds' success at science in the sub-problem of the research. For this purpose, frequencies and percentages were utilized. According to the findings of the research, it was found that "education status of the father" is the most predictive variable for the 15 year old students' science success in Turkey.