Class-based assessment aims to determine the progress and learning outcomes of students in grade VI SD Negeri Selapajang Jaya 2, by diagnosing learning difficulties of students in class, providing feedback or improvements in the learning process which aims to measure the extent to which students' ability to construct and reflect on a task or works through the collection of relevant materials by understanding the goals and desires of the VI grade students of SD Negeri Selapajang Jaya 2, so that the results of the construction can be assessed and commented on by the teacher in a certain period. So from class-based assessments and portfolios measuring the extent of the learning process that students have done in the learning process in the classroom. This study aims to determine how the application of class and portfolio-based assessments in Indonesian language lessons in grade 6 at SDN Selapajang Jaya 2. This study uses a qualitative approach, with the subject of a grade 6 teacher at SD Negeri Selapajang Jaya 2, data collection techniques using observation and interviews. The results of this study indicate that SDN Selapajang Jaya 2 has implemented class-based assessments in Indonesian language learning which consists of written tests, assignments, attitude assessments, and portfolio assessments, with the results of the data on the mean value of grade 6 students in language subjects. Indonesia.