This research aims to determine the effect of guided inquiry learning model to student’s learning outcomes in the subject matter of momentum, impulse and collision in class X SMA N 1 Percut Sei Tuan. This research is a quasi experiment with group pre test-post test design. The population in the study was all students of class X MIA SMA N 2 Percut Sei Tuan. The research sample consisted of two classes with technique cluster random sampling that is, a class X MIA-3 as class experiment and X MIA-4 as the control class, each one amount to 30 students. The instrument used is achievement test in the form of 8 essay. Based on data analysis obtain that there is effect of guided inquiry learning model to student learning outcomes in the subject matter of momentum, impulse and collision in class X SMA N 2 Percut Sei Tuan. Keywords: guided inquiry, dynamic fluid, learning outcomes