Objective:To assess the influence of a virtual simulation-based training system for composite resin filling on the knowledge acquisition, skill development, and overall learning experience of undergraduate stomatology students.Methods:Forty-one undergraduate students of grade 2019 majoring in stomatology were divided into two groups for preclinical training before their internships: the experimental group used a virtual training system for composite resin filling, while the control group watched instructional videos of the procedure. The two groups were compared for their first performance in composite resin filling during the internships and teaching feedback. The t-test and chi-square test were conducted for data analysis using SPSS 20.0. Results:After repeatedly using the virtual training system for composite resin filling, the students in the experimental group were able to master the key operational points of the procedure, all achieving high scores (an average of 91.77 points) with an average time of 10.39 minutes. During the internship phase, the experimental group and control group showed significant differences in the accuracy rates of instrument selection (85.71% vs. 40.00%), adhesive applying (76.19% vs. 45.00%), and layered filling (100.00% vs. 75.00%; all P<0.05). All the students unanimously recognized the value of the virtual simulation system and expressed their willingness to use it for preclinical training before internships. Nineteen students (90.48%) were satisfied with the learning experience with the virtual simulation training system. Conclusions:The virtual simulation training system for composite resin filling can improve students' understanding and proficiency levels of the technique before clinical internships, facilitating a smoother transition to the internship phase.