The optimal conditions of seeds germination for different cultivars was studied.The results showed that the suitable germination temperature varied with different cultivars.The optimal germination temperature was 20 ℃ for early flowering cultivars ‘Raizan No.1’,while for medium flowering cultivar ‘Rinzan No.2’and late flowering cultivar ‘Raizan No.3’,the suitable temperature were 18 ℃ and 15 ℃ separately.During the process of seed germination,lighting time and light constitutes didn’t have significant effect on germination rate.The experiments showed that the germination rates of three cultivars decreased greatly when germination temperature was over 24 ℃,especially for ‘Raizan No.1’.So,different pre-chilling treatments of ‘Raizan No.1’ were taken,in order to solve this problem.The results indicated that germination at 30 ℃ was accelerated by pre-chilling treatment at 10 ℃ for more than 10 days,germination rate was more than 75%,and it was 85.22% by the same pretreatment for 20 days,the same as optimal germination temperature 20 ℃.Whereas pretreatment at 3 or 5 ℃ had no promotive effects at 30 ℃ germination condition,germination rate was less than 40%.In conclusion,pre-chilling treatmet at 10 ℃ for more than 10 days was recommended to germination of Lilium×formolongi under high temperature conditions.