Abstract: Yield and yield components of 30 mid-season rice hybrids were studied in a joint regional field test in Fuzhou during 2007-2009.Data for identifying and selecting new stable,high-yield,mid-season rice varieties,as well as,establishing the cultivation technology was obtained.A differential analysis indicated that the difference on the variation coefficients for grain weight was the smallest among all,and the characteristics of the varieties tended to be relatively stable.The regression analysis showed that the 5 yield components positively correlated with yield,with the panicle number,filled spikelets per panicle and seed-setting rate significantly correlated.The partial correlation analysis showed that the panicle number,filled spikelets per panicle and grain weight had significant positive correlations with yield,while the partial correlation coefficient between spikelets per panicle or seed-setting rate and yield was negative,and not significant.The path analysis indicated that the direct effects of the panicle number,filled spikelets per panicle and grain weight on yield were all positive,and the filled spikelets per panicle contributed most greatly to the effect.All indirect effects of the panicle number,filled spikelets per panicle and grain weight on yield were negative,with the panicle number affected by the grain weight relatively high.When all factors were taken into consideration,the filled spikelets per panicle and panicle number should be the critical criteria for selection.However,at the same time,the grain weight and spikelets per panicle,as well as a relatively stable seed-setting rate could not be neglected.