Based on historical experiments of 46 Coupled Model Intercomparison Project Phase Five (CMIP5) models, all models are systematically evaluated, and 14 models with reliable performance are chosen to project seasonal precipitation proportion and its variability over China in the 21st century. It is found that the 14-model ensemble reasonably simulates the observed seasonal proportion of precipitation and its variability, while there are some differences between models and observations and between individual models. The differences are relatively large in western China and in the summer. For the whole country, seasonal precipitation proportion is the highest in the summer and lowest in the winter during the 21st century. The spatial pattern is region-dependent, for example, the proportion of precipitation in South China is larger in the spring than in the summer. Compared to that during 1986-2004, there is a significantly decreasing trend in the summer and an increasing trend in the winter and spring, whereas an increasing trend in the summer and a decreasing trend in the winter and spring are found for the Tibetan Plateau in the 21st century. In addition, the model results have considerable uncertainties with respect to the projection of precipitation in the middle and lower Yangtze River basin. The Representative Concentration Pathways 8.5 (RCP8.5) scenario shows a higher rate of seasonal change than the RCP4.5 scenario does. The variability of seasonal precipitation proportion has an increasing trend in all seasons, but there is no statistically significant difference at the 95% confidence level in the early, middle, and late 21st century compared with the 1986-2004 period.