Practicum performance assessment is defined as a tool for students’ performance during practicum that assesses thinking skills, laboratory skills, social skills and process skills which are believed to influence their academic self-concept in Environmental Pollution course. This research aimed to explore the implementation of character-based practicum performance assessment and its effect on students’ self-concept in Environmental Pollution course. The sample size for this study was 65 students who enrolled in the course at the Tadulako University in Palu, Central Sulawesi, and Sintuwu Maroso University in Poso, Central Sulawesi. Data of character-based practicum performance assessment were obtained from observations, while data for the students’ self-concept data were from questionnaires, and analyzed descriptively and statistically with linear regression analysis. The results showed that the value of character-based practicum performance was 81 under very good category and the value of self-concept was 79 under high category. The correlation value between character-based performance assessment and self-concept was 0.529 under moderate correlation category, and the calculated F value was 24.524, greater than the F-value or the critical F (4.00) with the significance value of 0.000. From those data, it can be concluded that the implementation of character-based practicum performance assessment has a correlation with students’ self-concept in Environmental Pollution course.