The study of algae culture collected in Brazilian waters was proposed due to the lack of literature on the subject: an attempt was made to develop a methodology to obtain algae culture and its purification. Several species were isolated from samples collected a Ubatuba and Cananéia (São Paulo) (Lat. 23º30'S - Long. 45º06'W and Lat. 25º01'S - Long. 47º54'W) by means of phytoplankton net and Van Dorn bottle. The following isolation techniques were employed after washing and concentration: glass capillary, inoculation of mixed cultures on Petri dishes with solid medium and positive phototropism. The isolated algae were kept in five different mediuns. Washing techniques were tested (centrifugation, "filter tubes" and re-isolation) , antibiotics and ultra violet radiation to obtain unialgal bacteria-free cultures were employed to obtain pure cultures. Five différents antibiotics, mixed in différents concentrations, were employed during several periods of expositions. The re-isolation proved to be the best method to obtain the purification of the cultures.