In order to screen rice varieties suitable for sowing in line under water cultivation in cold regions and clarify the adaptability evaluation indexes of agronomic and quality traits of sowing in line under water cultivation, 29 early japonica rice varieties in cold regions were used as materials, and random block experiment design was adopted to comprehensively evaluate the adaptability of sowing in line under water cultivation by using sowing in line under water adaptability coefficient, sowing in line under water adaptability index and comprehensive adaptability,combined with principal component analysis method. The results showed that there were 21 materials that can satisfy the adaptability coefficient, adaptability index and comprehensive adaptability of sowing in line under water simultaneously. Five factors including grain number per panicle, grain formation rate, economic coefficient, 1 000-grain weight and theoretical yield can be used as adaptability evaluation indexes of rice agronomic traits under sowing in line under water. The five factors of head rice rate, chalkiness degree, grain length, amylose content and rice taste score can be used as adaptability evaluation indexes of rice quality traits under sowing in line under water in cold region.