Penelitian ini bertujuan untuk mendeskripsikan keterampilan proses sains mahasiswa program studi pendidikan fisika pada materi hukum termodinamika. Populasi penelitian ini ialah mahasiswa program studi pendidikan fisika universitas Jambi angkatan 2017. Teknik pengambilan sampel menggunakan total sampling, jadi sampel penelitian ini yaitu seluruh mahasiswa pendidikan fisika universitas Jambi dengan total 91 mahasiswa di angkatan 2017. Indikator keterampilan proses yang diamati meliputi observasi, klasifikasi, membuat hipotesis, hubungan antar variabel, merencanakan percobaan, mengukur, memperoleh dan memproses data, analisis percobaan, komunikasi, serta kesimpulan. Data keterampilan proses diukur melalui lembar observasi, pada saat praktikan melakukan kegiatan praktikum hukum termodinamika. Data dianalisis menggunakan statistik deskriptif. Hasil dari penelitian ini, keterampilan proses sains mahasiswa fisika bervariasi dari kategori baik seperti observasi42,85%, klasifikasi 36,26%, mengukur 37,36%, analisis percobaan 32,96%, serta merencanakan percobaan 42,85%, kesimpulan 54,94%, membuat hipotesis 51,54%, dan hubungan antar variabel 42,85%. Selanjutnya untuk kategori tidak baik seperti komunikasi 39,56%, serta memperoleh dan memproses data 45,05%, Hasil ini menunjukkan mahasiswa belum menguasai keterampilan proses sains mahasiswa pada beberapa indikator. Oleh karena itu perlu adanya buku panduan pratikum berbasis keterampilan proses untuk meningkatkan keterampilan proses sains mahasiswa melalui kegiatan praktikum.This study aims to describe the science process skills of students in physics education program on the subject matter of thermodynamic law. The population of this study is the students of physics education program at Jambi University in 2017. The sampling technique using total sampling, so the sample of this study is all students of physics education program at Jambi university with a total of 91 students in 2017. The science process skills indicators observed to include observation, classification, hypothesized, relationships between variables, planning experiments, measuring, obtain and process data, experimental analysis, communication, and conclusions. Data science process skills was collected through observation sheets when the practitioner conducts the practicum thermodynamic law. Data was analyzed using descriptive statistics. The results of this study, science process skills of physics students varied from good categories such as observation 42.85%, classification 36.26%, measuring 37.36%, experimental analysis 32.96%, and planning experiments 42.85%, conclusions 54, 94%, hypothesized 51.54%, and the relationship between variables was 42.85%. Furthermore, for the bad category such as communication 39.56%, and obtaining and processing 45.05%. These results indicate that students have not mastered the students' science process skills on several indicators. Therefore, it necessary to have a science process skills based practicum guidebook to improve student science process skills through practicum activities.