The purpose of this study is to describe the metacognitive, cognitive, and socio-affective strategies used by the students and the implementation in practice. The type of this research is descriptive qualitative by using a case study. The data sources were carried out through informant and event. The subject of this research was the six good achievers of eight grade at the eight grade SMPN 4 Surakarta. The researcher used classifying data based on O’Malley taxonomy. The object of this research was focused on the O 'Malley learning startegies' used by good achievers to understand reading comprehension. The data collection techniques used in this research were open-ended questionnaire and in-depth interview. To analyze the data, the researcher used data reduction, data display, and drawing conclusion / verification. The researcher used triangulation to validate the data. The result of this research shows that almost all good achievers used O’Malley’s learning strategies to understand reading comprehension when they learning. This research found that good achievers prefer to use socio-affective strategy
