Backgrounds and objectives: Dental impressions present a risk to spread infections among dental practitioners and should be disinfected to prevent the spread of these microorganisms. Different disinfectant materials and techniques can be used to eliminate this threat. The purpose of this study was to evaluate the effect of some disinfectant materials with two different techniques on surface detail and dimensional stability of elastomeric impression materials. Materials and methods: Three dental impression materials were used in this study, Vinyl polysiloxane, Polyether and Vinyl polyether siloxane that were disinfected with sodium hypochlorite, Dettol and Cavex Impresafe by using two techniques, spraying and immersion methods for each. Results: The results of this study showed a significant difference of the dimensions between immediate and 48 hours after disinfection P<0.05 with the maximum change (1.5%) appeared with vinyl polysiloxane material when immersed in sodium hypochlorite for 10 minutes and stored for 48 hours, but this change was acceptable by the ADA. Polyether showed the least dimensional change of 0.05% after 7 hours from disinfection with Cavex impresafe and the latter caused the least change on the impression materials. Conclusion: Within the limitations of this in vitro study, it was concluded that dental impression materials can be disinfected without causing dimensional changes that affect the manufacture of dental prosthesis.