Abstract: In most rural areas of China, poverty was not a main problem anymore. However, the dietary health of rural residents has been ignored for long time. The changes of income have practical significance to the changes of the dietary health of rural residents. Based on the household production theory and the data of China Nutrition and Health Survey (CHNS), this paper adopted the Healthy Eating Index (HEI) to assess the dietary health of rural residents, and applied the Least Square Dummy Variables (LSDV) Model, Threshold Regression, and Instrumental Variable (IV) Regression to analyze the impacts of income on dietary health of rural residents, to compare the differences between different income levels, and to evaluate the rationality of the current poverty line from the dietary health perspective. Results show that: 1) there are significant differences in the dietary health between poor and non-poor rural residents，and the dietary health of non-poor rural residents is significantly better than that of the poor; 2) income has a significant positive effect on the dietary health of rural residents and the income effect on the residents under the poverty line is significantly higher than those above the poverty-line; and 3）without addressing the endogeneity of income, the effect of income on the dietary health may be underestimated. This paper suggests to raise the current poverty-line from 2 300 yuan per person (established in 2011) to 3 159 yuan to improve the dietary health of rural residents. In addition, sustained rural household income growth is still an important means to improve the dietary health of poor rural residents. Results also indicate that policy intervention, if any, should be cautious in using the present poverty line as the criteria to target beneficiaries.