This paper is going to cover female marriage immigrants from Vietnam, whose number is soared from the early 2000. In order to recognize their demands for social and economic adjustments, which are caused by the increasing number of Vietnamese girls in Korea in recent days, it is required to analyze the reasons of their marriage to Korean men. This paper will dissect the reasons as following: First, Vietnamese women have replaced Taiwanese men with Korean men as a spouse: Second, women from Mokong Delta have married Korean men increasingly in recent days: Third, Vietnamese women have had fantasy and penchant for Korean men due to Korean wave in Vietnam. From the facts that most of Vietnamese marriage immigrants are from the southern part of Vietnam and that they are low-educated, this paper will suggest that they should move to the rural areas. In addition, it will present welfare policies suitable for them, such as developing Korean language program for the low-educated, and subsidy and labour law to help their economic adjustment.