Objectives The aim of this study was to develop and evaluate the effect of a manual dexterity training program on manual dexterity, perception of self‐confidence, quality of cavity preparations, and ergonomic work posture of dental students prior to preclinical training. Methods Students in the first year of the undergraduate dentistry program (N = 63) participated in this study. The program consisted of eight phases in which students performed different types of activities. The dependent variables were: manual dexterity assessed by the modified Dental Manual Dexterity Assessment; self‐confidence to perform a preclinical procedure using the VAS scale; quality of Class I cavity preparation; angular deviation from the neutral position of the neck, trunk, wrist and distance between the student's eyes and the mannequin's tooth. These variables were evaluated at two different times: before and after the application of the program. The independent variable was the preclinical manual dexterity training program. After meeting the assumption of normality, the paired t‐Student test was performed, the significance level was 5%. Results The results showed a statistically significant difference in relation to manual dexterity (p < 0.001), self‐confidence (p < 0.001), quality of cavity preparations (p < 0.001), distance from the eyes of the student/mannequin (p < 0.001), deviation angle of the neutral position of the trunk (p = 0.007) and wrists (p < 0.001), with better results in posttraining. Conclusion It was possible to conclude that, in general, the proposed training positively influenced the self‐confidence, dexterity, quality of work, and ergonomics of the evaluated students.