Based on the meteorological data of Hubei Province dated from 1961 to 2008, the changing trends of primary heat resource elements of rice including the beginning and terminal day of ambit temperature, the interval days and accumulated temperatures between them, the daily temperature discrepancy during rice growing seasons were analyzed in detail and its impacts on rice production were also discussed. The results showed that the beginning day with daily temperature above 8℃,10℃ and 12℃ stably was advanced and the terminal day of 20℃ and 22℃ was delayed. The interval between them was extended and the accumulated temperatures were increased. The interval days and accumulated temperatures from the beginning day of 10℃ to the terminal day of 20℃ and 22℃ were extended and increased in most areas of Hubei Province. It indicated that the suitable stage of rice planting was extended. The daily temperature discrepancy during rice growing season and rice grain-filling stages was decreased, and the decreasing trend of eastern Hubei Province was more remarkable than that of western Hubei Province. Based on the analysis above, measures can be taken to improve unit rice yield by changing early maturing rice with medium or late maturing rice having long growth period and high yield. The area of double-crop rice cultivation can be extended to northern Hubei Province with abundant water and good irrigation, which will effectively increase the total rice production of Hubei Province.