This study investigated the influence of teachers' classroom management on pupils' motivation for learning and academic achievement in Kwara State. Descriptive survey design was adopted. The population was all primary teachers and pupils in Ilorin Metropolis, Kwara State. The sample size was 250 teachers and all pupils in their classrooms. One research questions and four hypotheses guided the study. The instruments used to collect data were researchers' developed instruments titled 'Teachers' Classroom Management Style Observation Scale (TCMOS) and Pupils' Motivation for Learning Rating Scale (PMLRS) with reliability coefficients of 0.82 and 0.86 respectively. Data collected were analysed using descriptive statistics, linear regression, t-test and Analysis of Variance (ANOVA). All hypotheses were tested at 0.05 level of significance. The results showed that there was significant influence of classroom management styles on pupils motivation for learning (F[subscript (1,248)] = 121.155, p < 0.05) and their academic achievement (F[subscript (1,248)] = 28.947, p < 0.05). It was therefore recommended that teachers should be encouraged to adopt appropriate classroom management to motivate pupils to learn for improved academic achievement. Also, courses on classroom management and leadership should be integrated into the teacher training curriculum while regular retraining of in-service teachers should be encouraged.