Science process skills are one of the skills that can be developed to prepare students for the 21st century. Preliminary studies have shown that students' science process skills are low, due to the lack of scientific inquiry implementation, the learning methods used are still focused on understanding concepts and solving problems cognitively, and practical activities are still rarely carried out. Therefore, this study aims to determine whether there are significant differences in science process skills using guided inquiry learning models and direct instruction. This study is an experimental study with a randomized pretest-posttest control group design. Sampling used a random sampling technique. Based on this technique, the samples obtained were class XI A using the guided inquiry learning model and class XI B using the direct instruction learning model. The research data were obtained from science process skills tests in the form of essay questions, namely pretest and posttest. Data were analyzed using an independent sample t-test. The results of the study indicate that there are significant differences in science process skills using guided inquiry learning models and direct instruction, and the guided inquiry learning model has an effect on improving students' science process skills.

 Keywords: Science process skills, guided inquiry, direct instruction