The family is the first founder of human personality, values and attitudes, and its emergence in the current style is one of the valuable characteristics of human beings compared to other creatures. The purpose of this research is to qualitatively investigate the causes of conflict between couples. The method of the current research is a qualitative method of the grounded theory type, which collects information through an inductive and exploratory research method. the statistical population of the research is all couples with marital conflict referring to counseling centers in Tehran in 1400-1999, who at least 1 year has passed since their marriage. The data collection tool was an in-depth interview. In the qualitative part, interviews were conducted with the interviewees who were selected purposefully and the statistical sample of the research reached saturation with 15 couples. Based on the qualitative analysis of this research, the causes of conflict between couples are categorized into six categories: the interference of significant others (spousal discrimination), past and present unresolved disorders and injuries, economic and financial issues, individual components of couples, crises and Milestones of life, virtual shelter. Based on this, it is necessary to pay attention to the role of other people's interference (differentiation of marital incompatibility), past and present unresolved disorders and injuries, economic and financial issues, individual components of couples, crises and milestones in life in order to reduce marital conflicts. It reduced the marital conflicts of couples.