To provide better cond’tions for fish culture, a study was undertaken to assess the best way of adapting mullet fingerlings (Mugil curema) to jreshwater. Mullets have been submitted to direct shock and gradual decrease of salinities of 12‰, 7‰, 3‰ and 2‰ (freshwater), with a survival varying from 65% to 100%. It was observed that weight varies in function of time, at salinities of 0,2‰, 3‰ and 7‰, and that of the fish médium with values of 14‰ and 30‰ (winter and summer) at Tamandaré, and 18‰ and 31‰ (winter and summer) at Itamarac‡, located res-pectively at the south and north of the state of Pernambuco coast.