To explore the chain mediating effect of teacher-child conflict and sleeping disorders between work intensification on vocal fatigue of kindergarten teachers, 847 kindergarten teachers in China were investigated using the Work Intensification Scale, Teacher-Child Relationship Scale (TCRS), Athens Insomnia Scale (AIS) and Vocal Fatigue Index (VFI). Data were analyzed by JASP 0.14.1 and structural equation model was built through Mplus8.3. It showed that there were significant differences in vocal fatigue of kindergarten teachers in areas, age and education level. Work intensification, teacher--child conflict and sleeping disorders were positively correlated with vocal fatigue of kindergarten teachers after controlling for demographic variables such as the nature of the kindergarten, geographic areas, gender, age and education level of the teachers. In the multiple mediation model, work intensification could directly predict vocal fatigue of kindergarten teachers significantly through the mediating role of sleeping disorders but not teacher-child conflict. Moreover, teacher-child conflict and sleeping disorders had a chain mediating effect between work intensification and vocal fatigue of kindergarten teachers. So the government and education authorities should reduce the workload of kindergarten teachers, vocal training should be included in the curriculum of preschool education in universities, and it's necessary to strengthen the pre-service and post-service kindergarten teachers' training about voice using so as to improve the health care awareness. Teachers should develop communication skills to create effective interactions between teachers and children, and good environment should be created by mindful training to improve sleeping.