Abstract: The study investigated the relationship between pre-service teachers’ classroom management style and senior secondary students’ performance in general mathematics in Rivers state Nigeria. A sample size of ninety four (94) final year pre-service mathematics teachers was used for the study. The census sampling technique was employed to draw the sample. Six research questions were answered and six hypotheses were tested at 0.05 level of significance. Two instruments were used to collect data namely the “Pre-service Mathematics Teachers’ Classroom Management Questionnaire” (PMTCMQ) and “Mathematics Performance Test Grade Inventory” (MPTGI).