Generally it is said that among the ethnic groups, such as Iranian Turkmen, there is an early pattern of the age at marriage. In other words, it is mostly claimed that ethnicity is a powerful force in reducing the marriage age. In order to study this issue, changes in the marriage age among Turkmen people especially those residing in Turkmen Shahrestan of Golestan province in the north of Iran have been explored by reviewing some anthropological reports and examining statistical sources such as censuses and sample surveys. The study revealed that the age at marriage among Turkmen was, however, early in the past, but at present both males and females marry relatively late. Among the two factors of modernization, that is, the literacy and urbanization, the changing pattern of marriage timing among Turkmen is attributable, in some extent, to literacy, but the relationship between urbanization and marriage timing is not clear. On the other hand, traditional norms and practices governing marriage practice such as endogamy, payment of bride price and other payments at the time of marriage ceremony along with population growth followed by marriage squeeze and restrictions in occupational opportunities during recent decades have had considerable influences on the marriage timing among Turkmen people.