Objective: To evaluate the influence of the incorporation of a polymerization catalyst to a light-cured pulpcapping material on mechanical behavior and physicochemical characteristics. Material and Methods: Differentpercentages (2 wt%, and 4 wt%) of diphenyliodonium hexafluorophosphate (DPI) were incorporated into theUltra-Blend Plus, a resin-modified calcium-based cement. The material without incorporation of DPI (0 wt%)served as control. Degree of Conversion (DC), Flexural Strength (FS), Elastic Modulus (EM), Water Sorption(WSp), Solubility (Sl), and pH of eluate at 24-h, 72-h, and 7-day storage times were measured. One-way ANOVA/Tukey posthoc tests were used to analyze the data (p <0.05). Results: For DC, FS, and EM, materials withdifferent % of DPI showed statistically significant differences, so that 0% provided the lowest values and 2% thehighest values. Materials with 0% and 2% of DPI provided statistically the lowest WSp, whilst material with 0%of DPI showed statistically the highest Sl. Conclusion: All materials provided statistically similar pH to eluatesregardless of storage time, although only materials with DPI at 2% and 4% maintained pH of eluates statisticallysimilar from 72 h to 7 days storage times. KEYWORDSLight-cured pulp capping material; Polymerization catalyst; Pulp capping.