Abstract: The heterosis and correlation of main yield characters in indica hybrid rice were investigated by way of 4?8 incomplete diallel cross design with four sterile lines and eight restorer lines. The results showed that the main yield characters had significant heterosis in indica hybrid rice. The heterosis for grain weight per plant (GWP), number of spikelets per plant (NSP) and number of grains per panicle (NGP) were significantly positive correlation between F1 and female parent, and GWP, straw weight per plant (SWP), NSP, NGP, seed setting (SS) and 1000-grain weight (GW) were significantly positive correlation between F1 and male parent. The correlation degree between F1 and mid-parent was the highest, then followed by that between F1 and high-parent, that between F1 and male parent, that between F1 and female parent. Except GW, other characters were significantly positive correlation between F1 and mid-parent heterosis and over-parent heterosis.