The aim of this study is to analyze physics students' problem solutions related to calculus-based physics problems. The sample of this study consists of 41 third-year university students studying in a physics education program. Two physics problems were posed to the students in the study. The students' problem solutions were analyzed descriptively. According to one of the results obtained from the study, most of the students calculated the curl of the force field and proved whether it is conservative or not. However, the students had difficulties while calculating the work done in the force field. In relation to this, some students tried to calculate the work using mathematical equations which are incompatible with the analysis of the unit systems and contrary to the nature of the vector quantities. Besides, it has been determined that students have difficulties with the limits and variables of integrals.