Abstract: Environmental factors related to climate change may affect the nutritional quality of cereals. The effects of the increase of CO2 concentration, temperature and precipitation caused by climate change on the nutritional quality of crops, especially on the protein content of grains in China, have not been quantified. Therefore, this study made a meta-analysis of the existing literature data of various experimental sites in China, and used the protein content data of wheat grains in China combined with meteorological data to evaluate the influence of key growth temperature on the protein content of wheat grains in the main wheat growing areas in China, by using a mixed linear model, fixed regression and random residual analysis, a linear mixed model with random intercept and slope was used in each region to calculate the average sensitivity of grain protein content at different stages of temperature (wheat total growth period temperature, vegetative growth period mean temperature, reproductive growth period mean temperature). The results of meta-analysis showed that the protein content in wheat grain was significantly increased by warming (P < 0.05), and the protein content in wheat grain was significantly decreased by increasing CO2 concentration. The effect of precipitation on protein content in wheat grain was complicated. Temperature increase can partially offset the negative effects of CO2 increase and precipitation on wheat grain protein. From 2010 to 2018, the average temperature in the growth period of wheat in all provinces showed an upward trend. In all the investigated research areas, the average temperature in the total growth period of wheat increased by about 1.27℃, and the change trend of the average temperature in different wheat growing areas was different. The grain protein content in different wheat producing areas in China mainly responds positively to the average temperature in the growth period, and the average temperature in the reproductive growth stage plays a leading role in the variability of protein content in wheat grains. Based on the results of this study, suggestions for adapting to climate change can be put forward for different regions in China. In Shandong, Jiangsu and Anhui areas, the protein content in grains is positively sensitive to temperature and significant (P < 0.05), which can develop into a wheat producing area with high protein content in grains under climate change. In Hebei, Henan, Shanxi, Shaanxi, Hubei and Xinjiang, the climate has a positive sensitive effect on the protein content of crops, but it is not significant (P > 0.05). In these areas, appropriate crop management strategies can be formulated according to local conditions to adapt to environmental warming. In the middle and lower reaches of the Yangtze River, due to the low temperature and lack of sunshine during wheat filling, protein content has always been low, which is not suitable for planting strong gluten wheat varieties, but weak gluten varieties with low protein content can be planted. In Sichuan Basin, wheat with low protein content can be developed and planted for a long time because of the low explanation of climate factors by grain protein content. The research results can provide scientific basis for the influence of climate change on protein content in wheat grains, and contribute to regional decision-making, and formulate appropriate adaptation strategies for climate warming, so as to promote sustainable agriculture and nutritional security in China.