Grain security should be a priority for the Chinese government when managing state affairs. The total rice production needs to remain stable at more than 200 million tons. However, there have been serious rice harvest losses, especially the harvest stage. In this study, the meaning of rice harvest losses was defined based on previous research findings on the definition of grain harvest losses and the realities in China. The current rice harvest losses in different areas in China were analyzed based on sampling survey data from 957 farmers in 10 provinces in China. On this basis, the main factors influencing rice harvest losses and their marginal effects were analyzed using the ordered multinomial logistic model. The survey found that 56.22% of respondents believed that rice harvest losses were 4% or lower in China, though there were differences among the province. The proportion of family rice-farming income, size of production area, level of mechanization, timely harvest, and operational meticulousness had negative effects on rice harvest losses. On the other hand, farmers' experience of employment as migrant workers had a positive effect on rice harvest losses. In addition, bad weather and short handedness during harvest significantly increased rice harvest losses.