%A 1923042004 Farihatul Hasnah %T THE IMPLEMENTATION OF ONLINE PORTFOLIO AND PAPER-BASED ASSESSMENT AND THEIR EFFECT ON STUDENTS? WRITING ACHIEVEMENT AND THEIR LANGUAGE ATTITUDE AT THE TENTH GRADE STUDENTS OF SMA MUHAMMADIYAH 1 NATAR %X The current research aimed to investigate i) the difference of the students? writing achievement between the students taught through online portfolio and those taught through paper-based assessment and ii) students' language of the implementation of the online portfolio. The quasi-experimental with nonequivalent pretest-posttest group design was used to compare the gain of writing achievement for both the experimental and the control groups. The subjects of this research were 23 first-grade students of SMA Muhammadiyah 1 Natar. The experimental group was taught through the online portfolio and the control group was provided with the paper-based assessment. The data were obtained from writing test and questionnaires. The data were compared using an Independent t-test through SPSS v.20. The data of attitude were analyzed using descriptive statistic. The result showed that there was a statistical significant difference of writing achievement between the students taught through online portfolio and those taught through paper-based assessment with significant level 0.05. The students indicated the positive language attitude. This suggests that teaching writing through online portfolio facilitates students to improve their writing. Keywords: online portfolio assessment, student's language attitude, writing skill %D 2022 %I LAMPUNG UNIVERSITY %L eprints65791