The aim of the present study was to evaluate the association between childhood dental experiences and dental fear in adulthood among dentistry, psychology and mathematics undergraduate students. A cross-sectional study of 1,256 students from the city of Belo Horizonte, Brazil, was performed. Students responded to the Brazilian version of the Dental Fear Survey (DFS) and a questionnaire regarding previous dental experiences. Both the DFS and the questionnaire were self-administered. Association was tested using descriptive, bivariate and multivariate linear regression analysis, with a 5% significance level. Dentistry undergraduates reported lower scores than psychology (p < 0.001) and mathematics undergraduates (p < 0.05) for all three dimensions of the DFS. Negative dental experiences in childhood was associated with dimensions of Avoidance (B = 2.70, p < 0.001), Physiological arousal (B = 1.42, p < 0.001) and Fears of specific stimuli/situations (B = 3.44, p < 0.001). The reason for first visit to dentist was associated with dimensions of Physiological arousal (B = 0.76, p < 0.01) and Fears of specific stimuli/situations (B = 1.29, p < 0.01). Dentists should be encouraged to evaluate the dental fear of their patients before treatment. The DFS has been found to be an effective instrument for this purpose.