[Objective] The study aimed to screen rational seedling raising date and seedling raising mode for plateau japonica rice,in order to reduce the effect of low temperature on seedlings. [Method]The seedlings of conventional japonica rice Hexi 22-2 and giant embryo No. 1 japonica rice were treated at day temperature 12℃ / night temperature 8℃ and day temperature 14 ℃ / night temperature 10 ℃,and the indicators including chlorophyll content,soluble sugar content,soluble protein content,survival rate,plant height,number of ≥ 1 cm roots,leaf wilting degree and aboveground dry matter weight were determined after treated for0,3 and 6 d,respectively. [Result]Chlorophyll content of seedlings decreased when treated by low temperature for a certain period; with the prolongation of treatment time,contents of soluble sugar and soluble protein in some low temperature treatments increased,while plant height,number of ≥ 1 cm roots and aboveground dry matter weight increased slowly,but the growth rate was significantly lower than that at room temperature; with the decrease of temperature and the prolongation of treatment time,leaf wilting degree increased. The comprehensive experimental results showed that with the increasing duration of low temperature,when two japonica rice varieties grew under the same low temperature,seedlings grew more and more slowly,probably because the lower the treatment temperature,the greater the damage on plants. Giant Embryo No. 1 had weaker cold tolerance than Hexi 22-2. [Conclusion]The study provides a theoretical basis for formulation of seedling raising technique of plateau japonica rice. [Objective] The study aimed to screen rational seedling raising date and seedling raising mode for plateau japonica rice, in order to reduce the effect of low temperature on seedlings. [Method] The seedlings of conventional japonica rice Hexi 22-2 and giant embryo No 1 japonica rice were treated at day temperature 12 ℃ / night temperature 8 ℃ and day temperature 14 ℃ / night temperature 10 ℃, and the indicators including chlorophyll content, soluble sugar content, soluble protein content, survival rate, plant height, number of ≥ 1 cm roots, leaf wilting degree and aboveground dry matter weight were determined after treated for0,3and6d, respectively. [Result] Chlorophyll content of seedlings decreased when treated by low temperature for certain period; with the prolongation of treatment time , contents of soluble sugar and soluble protein in some low temperature treatments increased, while plant height, number of ≥ 1 cm roots and aboveground dry matter weight increased slowly, but the g with the decrease of temperature and the prolongation of treatment time, leaf wilting degree increased. The comprehensive experimental results showed that with increasing of low temperature, when two japonica rice varieties grew under the same low temperature, seedlings grew more and more slowly, probably because the lower the treatment temperature, the greater the damage on plants. Giant Embryo No. 1 had weaker cold tolerance than Hexi 22-2. [Conclusion] The study provides a theoretical basis for formulation of seedling raising technique of plateau japonica rice.