The purpose of this study was to evaluate the color change of a silorane-based and two methacrylated-based resin composites upon exposure to bleaching agents, distilled water (control), 15% carbamide peroxide and 30% hydrogen peroxide for 3 weeks. The colors of all specimens before and after storage in the bleaching agents were measured by a spectrophotometer based on CIE Lab system, and the color differences thereby calculated. Data was statistically analyzed by ANOVA and Tukey’s test. The mean color change in silorane-based resin was significantly higher than that in methacylate-based resin composites regardless of bleaching agents (p<0.05). The groups treated with 15% carbamide peroxide and 30% hydrogen peroxide showed significantly different color change compared with the control group (p<0.05). In conclusion, the silorane-based resin composites exhibited more color change (ΔE) after exposure to the bleaching agents.