Objective To understand the current situation and main causes of neglect of urban migrant children in three regions of Yunnan Province, so as to provide scientific basis for reducing neglect and formulating intervention measures effectively. Methods According to the economic and educational level and other factors, multi-stage stratified cluster sampling was adopted to select three areas of Kunming, Dali Prefecture and Lincang City were selected as the survey points from September to December 2020. A related survey was conducted among 1 193 students by using the Constant Modulus Table of Neglect Evaluation of Urban Children and Adolescents in China. Results The total neglect rate of urban migrant children aged 6 to 11 in three regions of Yunnan Province was 40.7%(486/1 193), of which the neglect rate of urban migrant children was 40.80%(393/963), the neglect rate of non-urban migrant children was 40.4%(93/230). The neglect rates of urban migrant boys at all levels were significantly higher than those of girls, of which the difference in safety level was statistically significant(χ²=4.417, P<0.05). Except for medical treatment, the neglect rate of Han nationality was higher than that of ethnic minorities(χ²= 6.963, P<0.05), of which the differences in physical neglect and emotional neglect were significant(χ²= 6.963, 6.850, P<0.05). Compared with rural children in Yunnan Province, left-behind children in rural China, and corresponding indicators of children in China, the neglect degree of urban migrant children in Yunnan Province was significantly lower(6- to 8- year-old children t=20.281, 19.153, 13.616, P<0.05; 9- to 11-year-old children t=7.075, 13.101, 8.047, P<0.05). Conclusions Child neglect is less severe than what it was a decade ago, and the effects of relevant policies for migrant children are gradually emerging. The mode of family education has changed. The "involvement of parents in education" has gradually replaced "children working in cities with their parents" by "parents studying in cities with their children". However, the social integration and adaptation of young migrant children should be paid continuous attention. The gender gap in child neglect rates is smaller at the ethnic education level, and school and family education should be tailored to the local context and focus on parent-child participation.