Oyster is one of the commercially important shellfish species in the world, and oyster cultivation has been one of the most prevalent shellfish quaculture industries. Selective breeding researches and programs for several commercial oyster species are briefly reviewed and the progress made from these programs is summarized in this paper. Particularly, the achievement of genetic improvement for growth, yield and disease resistance in some economically important oysters (the Pacific oyster, American oyster, European oyster and Sydney rock oyster et al.) is outlined accordingly here. So far, some fast growth lines and disease resistant strains have already been created. Two strategies, mass selection or family selection, were employed in these sel ective researches and programs. Both of them have been proved effective and fruitful. The estimations of heritability for live weight and whole size were in the range of 0.25-0.69 and of 0.2-0.5, respectively. All these efforts and results clearly showed that the regular breeding theories and techniques were applicable to oysters. Hopefully, the developments of regular breeding technology and that of molecular biology technology are expected to create a new era for oyster breeding science and practices in the future.