Studies on wild oyster populations in the Santos region were started in March 1960, and in September of the same year work was begun on experimental culture. Several natural beds were found, the majority in the Bertioga Canal. Both the observations of wild populations and the experiments showed that the Canal is the most favorable location for oyster development. It was possible in the experimental work to show that both growth and survival rates are much higher there than they are in waters of higher salinity. Also the yield of meat per unit weight is higher in the Canal; about 1.5 g per centimeter of total length at the commercial size of approximately 8 cm. Two extended periods of fixation were found in the Canal, one in summer and the other from the end of winter through spring, although in the bay the fixation was practically year round. These results indicate good possibilities for a commercial oyster-culture industry. However, a bacteriological analysis of oysters from Canal beds showed coliform bacteria, so that provisions for purification should be made in any plans for development of oyster culture.