Xiu-Shui 117, a japonica cultivar and IR58, an indica cultivar were discovered to show compatibility in indica/japonica crosses. The spikelet fertility of F1, hybrids of 6 japonica/indica crosses, i.e. Xiu-Shui 117/IR58, Xiu-Shui 117/Er-Jiu-Feng, T8340/IR58, Shuang-Bai A/IR58, Nong-Liu 209A/IR58 and Liu-Qian-Xin A/IR58 was 85.9%, 88.4%, 81.1%, 76.5%, 74.5%and67.0%, respectively. The F1 hybrid of Xiu-Shui 117/IR58. greatly exceeded the higher parents in several traits, such as plant height, panicle length, the number of'spikelets per panicle and the grain yield per plant, etc. The compatibility of this cross was also present in the F2, and backcross generations. The results suggested that there may be some varieties which would show compatibility in indica/japonica crosses in both subspecies, but the extent of their compatibility might be different. Some problems were discussed about utilizing the heterosis of the F1 hybrids between indica and japonica.