<![CDATA[This study was aimed to determine the effect of Problem Based Learning in improving writing communication skill and students learning achievement. The design was pretest posttest non-equivalent. The samples were students in class VIIA and VIIC selected by purposive sampling. Quantitative data were obtained from the average score of the pretest, posttest and N-gain were analyzed by using t-test and U-test. Qualitative data were average score of written communication skill and analyzed descriptively. The result showed that writting communication skill in the experiment class had good criteria (78,40). The improvement of students achievement shown by the average N-gain of the experiment class (86,60) was higher than control class (55,10). Therefore, it can be concluded that Problem Based Learning improved writting communication skill and students achievement significantly. Penelitian ini bertujuan untuk mengetahui pengaruh Problem Based Learning dalam meningkatkan keterampilan berkomunikasi tertulis dan hasil belajar siswa. Desain penelitian adalah pretest-posttest kelompok tak ekuivalen. Sampel penelitian ini adalah siswa SMP Nusantara Bandar Lampung kelas VIIA dan VIIC yang dipilih secara purposive sampling. Data kuantitatif diperoleh dari rata-rata nilai pretest, posttest dan N-gain yang dianalisis menggunakan uji-t dan uji U. Data kualitatif berupa rata-rata nilai keterampilan berkomunikasi tertulis siswa diperoleh dari analisis data secara deskriptif. Hasil penelitian menunjukkan bahwa keterampilan berkomunikasi tertulis kelas eksperimen berkriteria baik (78,40). Peningkatan hasil belajar siswa terlihat pada rata-rata N-gain kelas ekperimen lebih tinggi sebesar 86,60 dibandingkan kelas kontrol sebesar 55,10. Dengan demikian, dapat disimpulkan bahwa Problem Based Learning meningkatkan keterampilan berkomunikasi tertulis dan hasil belajar siswa secara signifikan.Kata kunci : hasil belajar, keterampilan berkomunikasi tertulis, problem based learning]]>
