The aim of this study was to examine the preparation of science student teachers before teaching in English, and to determine their self-efficacy in teaching in English. Data were collected using the triangulation method, through questionnaires, interviews, and documentation studies on student teacher practicum portfolios. This was a descriptive qualitative study and data were analyzed using the interactive analysis method of Miles and Huberman (1984) which has three components of analysis, namely data reduction, data presentation, and drawing conclusions or verification. The results showed that there were 6 preparations made by science student teachers before teaching in English: 1) determine the topic of the material being taught and look for the material; 2) study the subject matter in depth; 3) compile lesson plans in English; 4) prepare tools and materials for teaching including handouts, props, demonstrations, and science practicum; 5) search for common terminology in science related to the topic being taught; 6) practice teaching science in English, namely doing teaching exercises in English. The results also showed that the science student teachers’ level of self-efficacy in teaching science in English varied from low to high: 45.8% had high self-efficacy levels; 39.5% had moderate levels; and 9.0% had low self-efficacy.
Keywords: self-efficacy, science student teacher, teaching preparation, readiness