Background & aim: The Increasing phenomenon of post-marital relationship in the society has had adverse consequences. One of the consequences, is the instability of family foundations and the disintegration of social cells (families). The aim of this study was to determine the formation process of meta-marital relationship from mens viewpoint.

Methods: The methodology of this study was grounded theory method. 16 men with purposive sampling method were selected as participants in Gachsaran city, Iran. The data was obtained through semi-structured interviews and was analyzed due to the three stages of "open, axial and selective" coding.

Results: Findings of the study were categorized in three major categories: the emotional disproportionate relationship-sexual between men and women's, and, socio-cultural structure predisposing of men and women's sexual dissatisfaction and incorrect criteria for choosing a spouse and one core category named extramarital relationship, hiding object was created.

Conclusion: Men Narrative participants indicated that due to spouse selection of "being unemployed, elder girl age, girl escape from his parental house, the divorced couple, and of man being widowed”, were are indications thay they were forced to be married. Also, due to “employed women and pressing sexual desire “was the tool selection. In most of these marriages, men and women had a great age difference, and initially there was no love among them. The prevailing of cold atmospherel and indifference in the marital relations caused led to the fact that they could not meet the emotional needs of each other. Moreover, the culture of modesty dominant over most of the Iranian families has banned the talk of sex and its quality not only in public environments such as schools, universities, radio and television, but also in the family and even between men and women as a "taboo", and these couples can not talk about the quality of their sex life with eachother. At this situation, the women with post-marital relationship have expressed their objections by hidden relationships.