The use of standardized patients (SPs) shows promise in tobacco cessation treatment (TCT) training by providing a simulated clinical environment for dental students to practice counseling skills with individuals trained to portray patients. The purpose of this study was to determine if there was a difference in attitudes, perceptions, and knowledge between dental students who received a lecture and practice sessions with SPs and those who received a lecture only. Dental students in an introductory clinical course at one dental school were invited to participate in the study by completing a pre and post questionnaire. The pre questionnaire was administered to all students prior to a tobacco cessation lecture. Students were group-randomized to either the intervention or control group. The intervention group completed the post questionnaire after the lecture and practice sessions with SPs, and the control group completed it after the lecture only. Of ninety-eight students who attended the lecture and were invited to participate in the study, a total of ninety-four from the two groups (96 percent) provided two linkable questionnaires for analysis. In the results, training with lecture and SPs increased the students' understanding of barriers, subjective norms, perceived skills, self-efficacy, and intentions to provide TCT more than those in the lecture only; however, it did not significantly increase their attitudes and knowledge. These findings suggest that using SPs is a valuable educational method to promote the provision of TCT by dental students and graduates.