Against the background of global warming, although the frequency of low-temperature disasters varies among different hazard-bearing bodies and areas in China, the intensity of such events does not diminish. Double-cropping early rice is the main crop in southern China, which is often affected by unexpected cold weather during sowing and transplanting. There have been numerous studies on low-temperature damage to various crops in southern China except for early rice during its sowing and transplanting. To reduce the yield loss of early rice, we studied the occurrence trends and the risk of spring low-temperature damage to early rice. According to the daily average temperature data of 178 weather stations from 1961 to 2010 and the Grade of Cold and Rainy Weather during the Seeding-Raising Stage of Early Rice, we studied mutation-related characteristics of spring low-temperature damage to early rice in early-rice cultivating areas in southern China. According to the mutational-analysis results, we evaluated the distribution of trends and risk of spring low-temperature damage to early rice during two periods (from 1961 to 1990 and from 1991 to 2010). The results showed that compared to the first period, the frequency of low-temperature disasters changed its trend from increasing to decreasing in the recent 20 years. The scope and size of the high value area of the risk index for low-temperature disasters and the probability for each level of low-temperature disasters were both decreasing. Mild low-temperature disasters showed the highest probability of occurrence and the highest probability of the decreasing scope. Our findings may serve as the basis for dynamic evaluation of the occurrence of low-temperature damage to early rice and for rational planning of early-rice planting.