This study was designed to clarify the optimal temperatures for growth in uniseriate thalli and foliose thalli of Pyropia tenuipedalis in the laboratory culture at 5℃ interval from 10℃ to 25℃ or 30℃. The optimal temperature of uniseriate thalli which used two-cell stage developed from a spherical cell were 15℃ and 20℃. And, the optimal temperature of foliose thalli which used young blade with the length about 6 cm was 15℃. It was suggested that these optimal temperatures of uniseriate and foliose thalli were related to the reduction of water temperature from autumn to winter.