Due to post graduate students’ theses make a major part of research projects in our country, attention to students’ research can be effective in solving the present problems. The aim of this study was to investigate the methodology of the post graduate students’ dissertations at University of Social Welfare and Rehabilitation Sciences (USWR). In this descriptive cross-sectional survey, the methods of all post graduate students’ theses in USWR that were defended from 2011 October to 2012 June were evaluated by using questionnaire. Fisher exact test was used; the data was analyzed by SPSS software using descriptive statistics. After, it revealed that 45% and 35% of students used descriptive- analytic and interventional methods, respectively. Consequently, descriptive, creative and providing valid and reliable questionnaire methods were obtained as 13.2%, 1.9% and 4.7% of thesis methodology. 40% of girls used interventional methodwhereas 58% of boys chose descriptive- analytic methodology. Moreover, interventional method was used more than other groups by younger students as well as students of faculty of Behavioral sciences in comparison to Rehabilitation and also Social welfare faculty. Fisher exact test showed a statistically significant relationship between type of faculty and thesis methodology (P=0.003). By considering the weight of students’ theses in researches, it is recommended that universities provide more educational, financial and supportive facilities for their students.