This study among other things examines the relationship between school plant planning and students’ academic performance in ten randomly selected secondary schools in Irele Local Government Area of Ondo State using descriptive survey research design. The sample consists of 110 respondents comprising 10 school principals and 100 students. Stratified and simple random sampling techniques were used to select the sample. Relevant data were collected by means of well structured questionnaires titled “School Plant Planning Questionnaire” for the school principals and Students’ Academic Performance Inventory for the students. Data collected were analyzed using percentages and Pearson product moment correlation. Five null hypotheses were tested at 0.05 level of significance. The study revealed that the levels of school plant planning and students` academic performance were relatively close, and as such students` academic performance was significantly related to instructional space planning, Administrative space planning, circulation space planning, and space for convenience planning. Based on the findings, it was recommended that authorities concerned should implement.