AIM: To evaluate the effect of administration of astaxanthin (ASTA) and fish oil (FO) on enzymatic antioxidant parameters of dental pulp tissue from healthy rats. METHODOLOGY: Thirty-two healthy Wistar rats were divided into four groups: untreated control, ASTA-treated (1 mg kg(-1) body weight), FO-treated (10 mg eicosapentaenoic acid per kg BW and 7 mg docosahexaenoic acid per kg BW) and FO plus ASTA-treated. A prophylactic dose was administered in each group daily by gavage, 5 days a week, for 45 days. After treatment, the rats were killed and all incisor dental pulps were removed. Superoxide dismutase (SOD), catalase, glutathione (GSH) peroxidase and reductase activities were determined. Data were compared by anova and the Tukey's post-test ( P  < 0.05). RESULTS: Treatment with FO, ASTA and FO plus ASTA caused a reduction in SOD and GSH reductase activities in dental pulp tissue compared to untreated control rats ( P  < 0.05). ASTA partially stimulated catalase activity. CONCLUSIONS: The preventive administration of ASTA and FO changed the enzymatic antioxidant system of dental pulp tissue, possibly by controlling oxidative stress.