The study determined the effectiveness of classroom observation on teachers’ performance. The descriptive correlational research design was used. The respondents of the study were forty-three (43) teachers from a population of forty-nine (49) in a public elementary school in Aklan, School Year 2021-2022. Majority of the respondents’ age ranged from 31-40 years old, most of whom were females, majority were Teacher I and master’s degree holders. The biggest number had been in service for five years, taught ESP, MAPEH, English, Araling Panlipunan, Filipino, Mathematics and Mother Tongue. A survey questionnaire was used to gather data on the personal profile of the teachers, classroom performance based on the instrument developed by the Philippine National Research Center for Teacher Quality, and effectiveness of classroom observation as perceived by the teachers themselves. Findings of the study revealed that the overall classroom performance of the teachers was outstanding. They perceived classroom observation as a very effective strategy to enhance classroom performance. Age and level of ICT literacy were significantly correlated to classroom performance of teachers. On the other hand, age, teaching position and level of ICT literacy significantly were correlated to perceived effectiveness of classroom observation. There was a significant relationship between perceived effectiveness of classroom observation and classroom performance. Hence, the more effective perceived classroom observation, the higher classroom performance.