Abstract: This study aims to find out is there a significant difference between the results of science process skills of students using project based learning with the results of science process skills of students using conventional learning. The research method used was Quasi Experiment. The instrument in this study used a science process skill test, in the form of observation sheets and multiple choice tests. Based on the results of research on the experimental class posttest data showing the results of the average percentage of science process skills, the experimental class received a percentage of 69.84% while the control class received an average value of 39.64%. Then the t-test calculated from the posttest value shows that tcount = 10.17 is greater t table (0.05) = 2, so that tcount> ttable. So it can be concluded that H0 is accepted, meaning that there are influences of science process skills of students using a project-based learning model. And based on the average value of science process skills measured by observation sheet is 79.37% with good categories, and the highest indicator in the experimental class is observing 85.41% and the lowest science process skills are hypotheses which is 75%. Abstrak: Penelitian ini bertujuan untuk mengetahui adakah perbedaan yang signifikan antara hasil keterampilan proses sains peserta didik menggunakan pembelajaran berbasis proyek (project based learning) dengan hasil keterampilan proses sains peserta didik menggunakan pembelajaraan konvensional. Metode penelitian yang digunakan adalah Quasi Eksperimen. Instrumen dalam penelitian ini menggunakan tes keterampilan proses sains, berupa lembar observasi dan tes berupa pilihan ganda. Berdasarkan hasil penelitian data postest kelas eksperimen menunjukkan hasil nilai rata-rata persentasi keterampilan proses sains, kelas eksperimen mendapat persentasi sebesar 69,84% sedangkan kelas kontrol mendapat nilai rata-rata persentasi 39,64%. Kemudian dihitung uji-t dari nilai postest  menunjukkan bahwa thitung = 10,17 lebih besar ttabel(0,05) = 2, sehingga thitung > ttabel . Jadi dapat disimpulkan bahwa H0 diterima, artinya terdapat pengaruh keterampilan proses sains peserta didik dengan menggunakan model pembelajaran berbasis proyek. Dan berdasarkan nilai rata-rata keterampilan proses sains yang diukur dengan lembar obsevasi sebesar 79,37% dengan kategori baik, serta indikator tertinggi pada kelas eksperimen yaitu mengamati sebesar 85,41% dan keterampilan proses sains yang terendah adalah hipotesis yaitu sebesar 75%.