Four major ethnic groups living in Thailand are differentas regards levels of fertility, and use of contraception and family planning. There are socio-cultural differences in each ethnic group. Values are factors affecting fertility and behaviour towards contraception. Thus, the socio-cultural factors should be considered and made know of in the project planning. The data shows that Thais have the lowest level of fertility whereas the Thai Muslims in the south have the highest level of fertility. For this reason, the level of fertility of this group should be decreased. However, Thais are the major group in the country so, their level of fertility should be decreased as well. A way of decreasing the level of fertility is the promotion of family planning especially contraception for the people. For Chinese, the level of fertility is influenced by a wife’s education and by age at marriage so, there should be a way to help Chinese women to decrease the level of fertility and to increase the age for marriage. Another factor is the gender value. Because Chinese prefer sons rather than daughters, education should be encouraged to support sexual equality which can reduce the size of Chinese families. For Thai Muslims, there should be an interest in ethnic sense and contraception that is contradictory to their religious principles. The religious leaders and big-sized families should be taught to cooperate with contraception policies. These processes take a long time and need patience to build up an understating of contraception in the future. (p. 236-238)