To induce an early spawning, the adult red sea bream, Pagrus major, were exposed to predesignated condition of photoperiod and water temperature during February 21 to June 30, 1988. Spawning began from April 20, a month earlier than that in the natural condition, when the photoperiod and water temperature were controlled at 14L: l0D and $17.0^{circ}C$, respectively, and the spawning continued until June 15, 1988. There were no particular differences between fish under the controlled condition and those in natural condition in terms of the fertilization rate, surface floating rate, the number of oil glouble and the hatching rate.