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This research uses the annual climate tendency rate and the linear trend method to analyze the characteristics of agroclimate resources over Sichuan Province and the growth period change of main crops in recent years. The results show that the beginning date of 10 ℃ advanced, the ending date of 10 ℃ postponed, and the accumulated temperature above 10 ℃ increased in most parts of Sichuan Province from 1961 to 2014Under this background, the seedling stages of maize and rice showed an advanced trend, with the rate being 66 days per 10 years and 35 days per 10 years; the mature period of maize has no obvious change in trend and the rice showed a postponed maturity period with the change rate being 24 days per 10 years; the growth periods of maize and rice both lengthened at different levels. The seedling stage of winter wheat had no obvious change; the mature period showed an advance trend, with the rate being 27 days per 10 years; the growth period significantly shortened, with the rate being 49 days per 10 years. In general, the increase of the accumulated temperature and the prolonged growth period provide necessary conditions for the crop varieties with a long growth period. Through the varieties selection and sowing date adjustment, we can sufficiently make use of the resource advantages to increase the crop yields.