B ackground: Composite resin restorative materials are increasingly used in modern dentistry because they fulfill the desired qualities, such as aesthetic appearance and good physical and mechanical properties. Exposure to the oral environment such as coffee drinks and mouthwash can affect the physical properties of the composite. Objective: The aim of this research is to determine the differences in the effects of alcoholic mouthwash, non-alcoholic mouthwash and chitosan on the surface roughness of nanofiller and nanohybrid composite resins after coffee immersion. Method: This research method uses laboratory experimental design with a pre-post test with control group design. The research was carried out on 40 samples of nanofiller composite resin and 40 samples of nanohybrid composite resin which were soaked successively in saliva for 24 hours, in coffee for 12 days, and in mouthwash for 28 days. Results: There was an increase in the surface roughness value of the nanohybrid composite resin restoration material and nanofiller composite resin after being soaked in Javanese Arabica coffee solution but there was no significant difference (p>0.05). The surface roughness value of the nanohybrid composite resin and nanofiller samples after coffee immersion increased significantly. The roughness value of the composite resin after soaking with mouthwash decreased. Conclusion: There was no difference in the effect of soaking in alcohol mouthwash, non-alcoholic mouthwash and chitosan solution on the surface roughness of the nanofiller and nanohybrid composite resins after being soaked in coffee. The group of mouthwashes that have the greatest potential for reducing the roughness level of composite resin are the non-alcoholic mouthwash group and distilled water.Keywords: Surface roughness of composite resin, mouthwash, chitosan, Javanese Arabica coffee, nanofiller composite resin, nanohybrid composite resin.