Anxiety is common in pediatric dental care, and affects the behavioral management of children. Animal-assisted therapy (AAT) has been shown to improve children’s behavior. However, few studies have applied this technique in dentistry. The aim of the present study was to evaluate the applicability of dog-assisted therapy to control anxiety during pediatric dental treatment. Twenty children were selected from the Pediatric Dentistry Clinic of the Pontifical Catholic University of Campinas (PUC-Campinas), Brazil. Participants were divided into two groups: Control (n = 11; visits = 16), in which children were conditioned by methods routinely used in the clinic; and AAT (n = 9; visits = 23), in which children had contact with a dog therapist first at the reception desk and then again inside the office. The dog therapist stayed beside the dental chair with the child throughout the procedures. Corah’s Dental Anxiety Scale (CS) and heart rate (HR) were used for evaluation of child anxiety. The results were tested for normality of distribution with the Shapiro-Wilk method, and subsequently analyzed in BioEstat 5.0. HR results were compared by Analysis of Variance (ANOVA) with Tukey’s test, and CS scores, with the Wilcoxon test. There was a significant reduction in HR in the AAT group (p = 0.0069). In the Control group, HR did not change before, during, or after treatment (p = 0.6052). Controls showed a significant increase in anxiety measured by CS before and after treatment (p = 0.0455). In the AAT group, there was no change in CS scores before and after treatment (p = 0.3739). AAT could be an alternative to reduce anxiety during pediatric dental care.