Introduction: There is a chance of cross-infection between dental clinics and dental laboratories with contaminated impression materials. Objective: To evaluate the sodium hypochlorite, UV radiation, aloe vera and microwave irradiation for disinfection of impression materials. Methods: The present research was done in the department of Prosthodontic. The study consists of 40 alginate impression materials which were disinfectant with Sodium hypochlorite, UV radiation, aloe vera and microwave irradiation for disinfection of impression materials. The pre and post bacterial count was evaluated. Results: The average post disinfection of microbial contamination showed that; Group 1 with sodium hypochlorite was more effective (359.1 at pre and 24.1 at the post) with lesser microbial count followed by group IV with microwave irradiation (336 at pre and 35.7 at the post), Group-III with UV radiation and least effective (342.4 at pre and 102.6 at the post) with Aleo vera (311.4 at pre and 82.1 at the post). Application of the one-way ANOVA test showed substantial variance (P< 0.05) in CFU in all groups. Conclusion: Authors observed that sodium hypochlorite is the better method of sterilization along with microwave irradiation. Whereas UV radiation and Aleo vera were also effective as a disinfectant. © 2021 Elsevier B.V., All rights reserved.