Goals of this study were (1) investigation of Iraninan couples' relationship based on Sternberg Model, (2) definition of dominant issues of couples' relationship, and (3) study of relationship between (triangular love relationships) with marital satisfaction and demographic variables. Data were collected from 66 couples (young and middle) chosen through available sampling method. Subject completed three instruments: (1) triangular love scale, (2) Enrich questionnaire, and (3) demographic characteristics scale.Analysis of data showed that there were significant differences between young and middlege couples in commitment and passion, but not in intimacy. Pillai's effect through paired t-test by Benferony correction reveald that in the middleage couples, commitment, and in young couples, passion was pre-eminent components.Study of available demographic variables showed that love relationship is predicted by level of education, Job and marriage duration, but not with age and number of the members of couples' family.Furthermore, result indicated that love relationship predicted the marital satisfaction in terms of the following issues: marital communication, sexual relation and personality issue.No meaning full correlation was detected between love relationship and others variables of marital satisfaction.