Abstract The growth of juvenile Japanese flounder Paralichthys olivaceus (Temming et Schlegel) exposed to various feeding and temperature regimes was studied in the laboratory. The temperature limits for growth were estimated from about 9 to 32°C, and highest growth rate was observed at a temperature of 25°C. For fish of an initial total length of about 3 cm, exposed to temperatures between 10 and 30°C with unlimited food, the daily growth rate in length (dL; mm·d −1) was described as a function of temperature (T,°C) by the equation: dL=0.005 T 2 − 0.0000046 T 4 − 0.35. Fish fed with mussel meat or mysids displayed similar protein conversion efficiencies. The relationship between condition factor of the fish and the proximate body composition of the fish is reported.