This study is aimed to describe the implementation of buzz group technique on enhancing students' activeness and writing skill of hortatory exposition text at the eleventh grade students of MA AL-KHORIYYAH Semarang, Indonesia. The result of this study found that buzz group technique could help students to be more active and able to enhance their writing skill of hortatory exposition text. This could be seen from the hortatory text produced by students were improved in every cycle. Using the writing asessment criterion modified from Alderson and Lyle (2002) the average of students' score was 67. 5 in the pre-cycle, which meant fair. And the observation result of students' activeness was 40%, it also meant fair. In the first cycle, the students' test got 81, whereas the observation of students' activeness score got 70%. Based on the result of first cycle, it showed good. And in the second cycle students' test got 87, and the observation of students' activeness score got 85%, it meant excellent. Teaching learning process ran well.