The temporal and spatial changes of crop diseases and insect pests were investigated based on the statistic data of occurrence area as well as planted crop areas data during the last 20 years in China. Meanwhile, the relationship between crop diseases and insect pests’ occurrence and climate were examined in this paper. Results showed that the trends of crop diseases and insect pests’ occurrence area and rate significantly increased by 8.52×10⁶ (hm²·time)/a and 0.05%/a, respectively (p<0.01). Spatially, Shandong and Henan had the largest planted crop area and occurrence area, whose occurrence area both reached more than 3.0×10⁸ hm²·time. Twenty-two years averaged, crop diseases and insect pests occurred all over the country, but experienced uneven pattern. The most serious province (autonomous region or municipality) is Shanghai, followed by Zhejiang and Jiangsu. Furthermore, the trends of crop diseases and insect pests’ occurrence area rate increased in all of the studied provinces in China. Shanghai (0.17%/a) and Zhejiang (0.12%/a) owned the largest two crop diseases and insect pests’ occurrence area rate, while Inner Mongolia, Xinjiang Uygur autonomous region, Gansu, Qinghai, Sichuan and Yunnan had the smaller increasing trends. Therefore the increasing trend of crop diseases and insect pests’ occurrence area rate descended from the coast to the inland. Out of the 28 provinces investigated, there were positive correlations between the anomaly of insect pests’ occurrence area rate and the anomaly of mean annual temperature in 25 (89.3%) provinces and were significant positive in 13 (46.4%) provinces (p<0.05), but no significant correlations with that of precipitation in most provinces.