Research Findings: This study investigated the relationships between effortful control and early literacy and mathematics achievement. A total of 181 children (85 girls and 96 boys) from rural China were assessed when they were in Grades 1 and 2. Path analyses controlling for maternal education indicated that effortful control at the beginning of Grade 1 predicted incremental achievement in literacy and mathematics at the end of Grade 1 and mathematics achievement at the end of Grade 2. Growth in effortful control during Grade 1 also contributed significantly to the prediction of both literacy and mathematics achievement at the end of Grade 2. Although girls performed significantly better than boys in literacy achievement, gender did not moderate the relationships between effortful control and literacy and mathematics achievement. Practice or Policy: Children's effortful control appears to be an important predictor of early literacy and mathematics achievement. Findings suggest that children's effortful control should be fostered during the preschool and early years of formal schooling, and this can be done in both home and school contexts.