This research aimed at studying the effect of process writing approach on grade 11 students’ paragraph writing performance and their perception on writing: the case of Mekane Eyesus General Secondary and Preparatory School. The study used a quasi - experimental design. The participants of the study were two sections of grade eleven with thirty-six and forty students these sections were selected based on simple random sampling technique. After selection, they were assigned as experimental and control groups using lottery method. And the intervention was given in the students’ class room. The control group was taught paragraph writing as usual, whereas the experimental group was taught paragraph writing through process writing approach. It was held for two month and four days in their regular classroom. The teaching material for the experimental group was\ designed from grade 11 students’ English Text Book based on process writing approach, whereas the control group used their normal Text Book as usual. Data was collected through writing tests and questionnaire. The writing test was computed and analyzed using SPSS version 25.0. Moreover, the questionnaire was analyzed in percentage. As the p- value of pretest result has indicated that there was in significant difference between the two groups of students, it was observed that the two groups were at the same level in paragraph writing performance before the intervention of the study (the p- value 0.75> 0.05). However, the posttest means statistics indicated that there was significant difference between the two groups of the students after the intervention. Since the p-value for the posttest paired samples difference t -test significance at 0.00 is lower than the standard significance level set at 0.05, it can be concluded that there was a significant difference between the two groups of students. Moreover, the pre-intervention questionnaire showed that students had negative perception about writing, but after the intervention they changed and developed positive perception on writing. Therefore, the result showed that process writing approach was relevant for the students to improve their performance of paragraph writing skill and to develop positive perception on writing skill. As a result, it was recommended that process writing approach should be considered in teaching writing skill to activate and develop students’ paragraph writing competence and perception.