Climate change is generally accepted to be a critical problem. It affects crop growth stages through changes in sunlight, heat and moisture. Our objective is to investigate the development of winter wheat growth stages under climate changes in northern China to determine possible causes of changes. Methods: Based on data of winter wheat growth stages and meteorology, we used multiple stepwise regression+residual interpolation to determine changes in winter wheat growth stages in northern China since 2000. Changes were investigated for two periods: 1971-1980 and after 2000. Important findings: The north part of northern China, including Beijing, Tianjin, Hebei and Shanxi Provinces, showed a significant warming and drying trend. In Henan and Shandong Provinces, temperature and precipitation had increased and sunlight had decreased. Jiangsu and Anhui Provinces also showed a trend of decreased sunlight and increased annual average temperature and accumulated temperature over 10°C; however, the changes were small. Variations in climate cause changes in the growth stages of winter wheat. Compared to the 1970s, the sowing period had been delayed about 7-10 days after 2000 in most parts of northern China except Jiangsu and Anhui Provinces. The greening stage had advanced in the southeast, but was delayed in the northwest part of northern China. The jointing stage had advanced in northern China, especially in Beijing, Tianjin, Hebei, Shanxi and Shandong Provinces. It postponed the heading stage about 2-15 days. The harvesting stage had been postponed in most parts of northern China by 5-10 days. Variations in climate factors, mainly sunlight, temperature and precipitation, are the main influences on winter wheat growth stages. Greening and jointing stages showed significant correlations to annual average sunlight hours. An increase of annual average temperature more strongly affected the heading stage. An increase of accumulated temperature over 10°C can postpone maturity of the stage. Precipitation can promote the stages of jointing and heading.