Nowadays, the increasing class size is a growing concern among State Universities and Colleges of the Philippines. The study attempted to determine the academic dimensions of the student performance across class size among sophomore college students in Mindoro State College of Agriculture and Technology-Calapan City Campus. Descriptive-comparative method of research was employed in the study. Record analysis was used to gather the academic performance in English, Filipino, Mathematics and Natural Science of the sixty-five subjects who belonged to small, average and large class sizes selected through stratified random sampling technique. Descriptive statistics such as frequency, percentage and mean were utilized to describe the performance of the students in four disciplines. Results showed that students perform best in Filipino compared with their performances in English, Filipino, Mathematics and Natural Science across various class sizes. Using F-test analysis, the study found out that students who belonged to small class size differ significantly in their performance in English, Filipino and Natural Science. This result was similarly noted among students who belonged to both average and large class sizes. Further, results revealed that student groups differ significantly in their performance in four disciplines across class size. Generally, with these results, it can be inferred that class size has influenced differences in academic dimensions of student performance and production of their learning.