Qualitative and Quantitative research-methods are different in some aspects but they complement each other in other aspects, as well. Following widespread criticism of qualitative and quantitative research methods, there is increasing trend in using mixed research methods in social sciences in general and political science in particular. Most advocates of pluralism attempted to fill the gap between qualitative and quantitative methods using the mixed research methods. The present research takes into consideration the introduction and definition of mixed research methods. Then, it tries to discuss different models and paradigms of mixing qualitative and quantitative methods and their advantages and disadvantages. Finally, it considers the outlook and future of mixed research methods in political science.