This study was designed to investigate the relationship between teachers’ classroom leadership styles and students’ achievement motivation in Obio-Akpor Local Government Area of Rivers State, Nigeria. Three research questions which were transformed into three hypotheses guided the study. The study adopted a correlational design. From SS II student population from 14 public senior secondary schools, 400 students were randomly selected and presented with two research questionnaires titled, “Teachers’ Classroom Leadership Style Questionnaire” (TCLSQ) and “Achievement Motivation Inventory” (AMI) adopted from Muthee and Thomas (2009). The TCLSQ and AMI had reliability coefficients of 0.83 and 0.86 respectively. Relevant data collected were analyzed with Pearson Product Moment Correlation Statistics. The results of the findings showed that, there was a positive and moderate relationship between autocratic leadership style and students’ achievement motivation, which was statistically significant. In addition, there was a positive but low relationship between teachers’ classroom leadership style of laissez-faire and students’ achievement motivation, which was however, also statistically significant. Finally, it was also found out that, there was a significant but positive and moderate relationship between teachers’ classroom democratic leadership style and students’ achievement motivation. Based on these findings, it was recommended among others that, teachers adopt leadership styles that will bring about optimal achievement motivation among students.