This paper reports the agronomic traits and standard heterosis(SH) of 27 indica/javanica hybrids Pei'ai 64S(Indica rice,a thermo-sensitive genic male sterile line) and Javanica rice at Changsha.In general,there are no significant difference in grains per panicle and theoretic yield per hectare but significant difference at 1% level in the other traits between indica/javanica hybrid and check;comparing with the check,the indica/ javanica hybrids have positive SH in culm height,panicle length,spikelets per panicle, grains per panicle and 1000-grain weight;and negtive SH in days to flower,effective tillers per plant,seed set,theoretic yield per hectare,actual yield per hectare.For the individuals,the hybrids with SH of theoretic yield per hectare>40% possess 11.1%,the hybrids with SH of actual yield per hectare >40% occupy 3.7%.The utilization method of iavanica resouces is discussed.