Abstract: The safe date for full heading is important for arranging seeding and planting of late rice. By analyzing daily average temperature during September and November in the past 45 years of three representative districts from north to south of Jinhua city (Dongyang， Wucheng and Wuyi) combining MannKendall jump detection and sliding ttest method， the changing year of safe date for full heading was determined to be 1999 for indica and 1991 for japonica. Basd on the indexes commonly used in production， the safe dates for full heading before and after changing year (1999 for indica and 1991 for japonica) with assurance rate of 50%， 80% and 90% were compared respectively. The average safe heading date of indica after 1999 was found to be universally delayed for 5 to 6 days， and that of japonica after 1991 was found to be universally delayed for 6 to 10 days. Thus， present study proposed another set of safe dates， which were September 14， September 16 and September 14 for indica in Dongyang， Wucheng and Wuyi respectively， being 4 days later than commonly used in production， and were September 24， September 24 and September 23 for japonica in Dongyang， Wucheng and Wuyi respectively， being 2 or 3 days later than commonly used in production.

Key words: Jinhua city, late rice, safe date for full heading