High prevalence of malaria in Southeast Asia including Thailand is believed to be a major public health problem to the population in this area since time immemorial. Adaptation of the population in this area following the principle of natural selection coupled with genetic disorders can be expected. Some good examples for natural selection of malaria are the co-existence of high prevalence of thalassaemia as well as glucose-6-phosphate dehydrogenase deficiency. In this report, general aspects of some important genetic disorders and malaria in Indo-China area (Thailand, Laos, Cambodia, Myanmar, Vietnam, Yunnan and Manipur) are summarized and discussed