Role-Play is successful to improve the students' speaking ability. Based on the qualitative and quantitative data, the use of classroom English helped the students to be more familiar with English. The vocabulary and pronunciation practices and role play performances also helped them to enrich their vocabulary knowledge and build their fluency and accuracy. In addition, Role Play is a useful technique to enhance students' communication. The objective of this research is to improve or develop Grade 9 students' speaking ability by using Role Play technique in Worebabo General Secondery and Higher Preparatory ~ . School. The participants were Grade9 students of Worebabo General Secondery and Higher Preparatory School in the academic year of 2008 E. C. The research design is quazi-experimental design which is none-equivalent with in a pre-test before the interventio7: and a post-test after the intervention and sampling technique is purposive sa1';ing. The data are in the form of field notes, observation, questionnaire, pretest and posttest. Meanwhile, the quantitative data are collected through assessing the students' speaking performance by comparing the means of the pretest and posttest. These data are the students' speaking scores. The procedure of the research consists of planning, acting, and reflecting. The results of this research shows that the use of Role-Play to develop students- speaking skills. Based on the quantitative data, the students' mean scores for