Hemophilia A and B, inherited as X-linked recessive traits, are the most common hereditary hemorrhagic disorders caused by a deficiency or dysfunction of coagulation factor VIII (FVIII) or FIX, respectively. Hemophilia is prevalent worldwide, without ethnic or geographic limitations, and remains a life-threatening and often disabling condition. Advances in molecular medicine in this century have markedly improved hemophilia treatment. However, management is still largely inadequate in developing countries. Therefore, carrier detection and prenatal diagnosis remain the key steps for the prevention of the birth of children with hemophilia in developing countries where patients with this coagulation disorder rarely live beyond childhood. Carrier detection and prenatal diagnosis are possible by direct or indirect genetic analysis of the F8 or F9 genes. In countries with more advanced molecular facilities and higher budget resources, the most appropriate choice in general is a direct strategy for mutation detection by prescreening techniques or direct mutation detection. However, in countries with limited facilities and low budget resources, carrier detection and prenatal diagnosis are usually performed by linkage analysis with genetic markers. This article suggests the possibilities of genetic diagnosis and a feasible strategy for carrier detection and prenatal diagnosis in families with hemophilia A and B in developing countries.