Abstract: 【OBJECTIVE】The research was made in order to determine the biological characteristic and cultivation techniques of hybrid rice Yiyou 99. 【METHOD】The data of regional trial, production experiment and multiple-point demonstrations of Yiyou 99 in fujian province were analyzed, the biological characteristics were analysed and high-yield cultivation techniques was put forward.【RESULTS】The results of regional trials by two years showed that Yiyou 99 had high-yield、good-quality and high-adaptability. The analysis of correlation and path showed that the effective panicle per area and grain number per panicle had a greater effect on rice yield, but they had indistinctive correlation with yield. seedset also had a greater effect on rice yield,and had apparent postive correlation with yield, 1000-grain weight had a smaller effect on rice yield,and had indistinctive correlation with yield. 【CONCLUSION】Based on suitable rice density,Cultivation strategy for high yield should be taken to accelerate seedset and grain number per panicle, and establish perfect high-yield colony to coordinate ear-kemel structure.