In recent years, qualitative research, or what ever has been known as a qualitative inquiry, increasingly has prevailed within social science, educational psychology, clinical psychology and educational research. Providing a precise and specific definition is difficult because in the analysis of the qualitative data we often use different techniques, which are based on various theoretical views. General characteristics of qualitative research are: emphasizing on discovery and description, not to use random sampling and selecting the sample on the basis of research purpose, emphasizing on the study of phenomena within their natural contexts, considering the researcher as one of the research instruments, presenting data as words, actions or pictures analyzing data as an inductive analysis and during doing the research, providing a descriptive and narrative report from research results, a deep and multi aspects analysis of a case, emphasizing on the role of personal meaning etc. The different methods of a qualitative research are: ethnography, grounded theory, conversation analysis, discourse analysis, and narrative analysis. The Present paper defines a qualitative research and reviews its philosophical and theoretical bases. In addition, different kinds of qualitative research methods will be briefly introduced.