The ectoparasitic mite fauna of non-poisonous snakes from the Estado de São Paulo was surveyed during the period of March, 1976 to September, 1979. Considerations are made about the systematics and ecology of the genera studied. A total of 1969 snakes belonging to 30 genera was examined. This study also includes data on multiple parasitism, diversity of the mite fauna, abundance of each genera of mite, for the 4 families and 7 genera of mites.