Objective To assess the outcome of the step-by-step teaching method in dental skill training of veneer preparation. Methods Forty dentists, who want to learn the veneer preparation technique, were recruited into this study, which was a prospective, double-blind and randomized controlled trial. The participants were randomly allocated to either the experimental group (n=20) or the control group (n=20). They learned veneer preparation under different training course structures. For the experimental group, the step-by-step teaching method was used, of which the course was divided into four steps according to the procedures of veneer preparation: incisal preparation, facial preparation, interproximal expansion, and finishing and polishing. Every step consisted of the teacher's lecture, the teacher's demonstration, and the learner's practice. For the control group, the all-in-one teaching method was used, of which the course comprised three steps: the teacher's lecture, the teacher's demonstration, and the learner's practice. Every step was carried out independently in turn. Thereafter, the training outcome was evaluated by the learners and teachers. The quality of preparations was evaluated by two experts. Results For the outcomes of the step-by-step and the all-in-one teaching methods, the learners' assessments were (4.35±0.67) and (3.40±0.75), the teachers' assessments were (4.67±0.58) and (3.33±0.58), the quality of preparations assessed by the experts were (7.93±1.03) and (6.60±1.29), respectively. In terms of each evaluation index, there was a significant difference between the two groups (P<0.05). Conclusions The step-by-step teaching method can improve the outcome of dental skill training of veneer preparation. The teachers and students had a higher preference for the step-by-step teaching method.