National grain security plays a critical role in national economy and the people’s livehood. In 2003-2013, China had achieved ten-year consecutive grain production increase that had never appeared in history and attracted a great deal of attention in the worldwide. Till 2015, the grain production has been experienced by the twelve-year consecutive increase. The purpose of this paper is to detect the spatiotemporal patterns and the main contributions of the ten-year consecutive grain production increase from 2003 to 2013. Based on factors contribu-tions analysis and GIS, this paper analyzes the situation and spatiotemporal differences of grain output growth at the national level and the provincial level, with the data of planted area and yield per unit area. The spatiotemporal patterns and the main contribution factors of China’s grain output increase were discussed at the multiple-levels including provincial level and national level. The results showed that: 1) the output growth of rice, wheat and maize (which are called “three major grain crops”) were the main reason of the grain output growth at the national level, whose contribution rate in the total grain output growth was 105.73% due to the decrease of other grain crops such as soybean, broomcorn, millet, etc; 2) maize was the biggest contributor in three major grain crops in 2003-2013, whether the rate of increase (88.63%), contribution rate of grain output growth (56.70%), the speed of incresase (1 026.59×10⁴ t/a) or the universality (29 provinces, municipalities and autonomous regions) of grain output growth, rice was the second, and wheat was the last; 3) at the national scale, the grain output growth caused by the promotion of yield per unit area accounted for 64.50%, which was more than that caused by the expansion of planted area (35.50%); 4) as to the crops, the output growth of rice and maize relied on the expansion of planted area, and the contribution rate of planted area was 56.59% and 64.83% respectively, whereas the output growth of wheat relied on the increase of yield per unit area which has the contribution rate of 73.21%; and 5) the grain output growth appeared in most of provinces during the 10 years, and the provinces in Northeast China, North China, the Huang-Huai-Hai Plain, the middle reaches of the Yangtze River had more significant increase. In general, the main regions with ten-year consecutive grain production increase were the Northeast China Plain, the Huang-Huai-Hai Plain and Xinjiang. The expansion of planted area and the increase of yield per unit area were both significant contribution factors to the grain output growth in 2003-2013, whereas the role of yield per unit area was more obvious.