Emergency remote teaching has been widely implemented in the education system worldwide to cope with the COVID-19 pandemic. Drawing upon data from a cross-sectional survey conducted in eight middle schools in eastern China (a sample size of 1,550 students and 1,550 parents), we employed multiple linear regressions with school fixed effects to examine the associations among student affective engagement, parental involvement, and teacher support in an emergency remote teaching environment. Our results show that higher levels of parental involvement and teacher support are associated with higher levels of student affective engagement with teacher support presenting the strongest relationship with student engagement. These findings contribute to the understanding of emergency remote teaching in different countries where schools and individual households devise varying strategies and solutions.