Learning written language in primary school is still low. This problem influence by teacher ability in written language learning. This study employed mixed method both quantitative and qualitative approaches. Semistructure interview was conducted in data gathering. Furthermore, the data were analyzed using qualitative analysis. The subjects of this study were six elementary school teachers, six elementary school supervisors, and six lecturers. Quantitative data was obtained through a questionnaire filled by 303 elementary school teachers at grade 4, 5 and 6 in Padang, West Sumatra Province. The data were analyzed using quantitative descriptive analysis with Statistical Package for Social Science (SPSS) software. This study constructed a competency framework required to be mastered by teachers in written language learning in Indonesian subject in elementary school, namely competency of cognitive, affective and psychomotor aspects.