Abstract: The effects of the combination of luteinizing hormone-raleasing hormone ono-logues, des-CIy¹⁰-( D-Ala⁶)-LHRH ethylamide ( LTR.H-A) with pimoaide ( PIM )，adopamine antagonist, on induced ovulation in loaeh during spawing season were inves-tzgated.Ahigh rate of ovulation. (nearly 100%)was ohseri ed within 24 hours when and LHRH--A were in jeeted aimultan eously，The rate of ovulation is much higherthan the ordinary fish pituitary injection groups. The effectiv a dasuge is PINT 0 .5g十LHRH- A 0.05g/g body weight. The effect o# injection PIM and LIIRH-A injectedsimultaneous行is better than that injected separately. If PIM+Iow dose of LHRH-A( D . gg bod.yweight) was injected twice with interval of 24 hours apart, the highrate of ovulation would be obtained. These results ret era the facts that P1M poentiatesthe effects of LHTtH- A an induction of ovulation in loach.