Background-Heat-cured PMMA are used for fabrication of dentures. Surface roughness of denture is an importantfactor determining plaque deposition. We aimed to determine the effect on the surface roughness of heat cure acrylic resin after immersion in four different disinfectant solutions viz. 2% chlorhexidine, 2% glutaraldehyde,2% sodium hypochlorite, and a novel disinfectant solution. Material & methods- Forty-eight specimens made of heat-cure denture acrylic resin were equally divided into 4 groups: Group 1- 2% chlorhexidine disinfectant solution; Group 2- 2% glutaraldehyde disinfectant solution; Group 3- 2% sodium hypochlorite disinfectant solution; Group 4- a novel disinfectant solution (a combination of hypochlorous acid (0.05%) and electrolyzed oxygenated water (99.95%) disinfectant solution). In each group, specimens were further subdivided into 2 subgroups. In subgroup A and B, the specimens were immersed for 10 minutes and 6 hours respectively. Specimens were examined under stereo-microscope™. Results- After immersion in the respective solution, no significant change in surface roughness was seen in group 1A, 1B, 2A and 2B (p-value>.05) whereas a significant increase in surface roughness was observed in group 3A, 3B, 4A and 4B (p-value <.05). Immersion for longer period caused significant increase in surface roughness only in group 4. Conclusion-10-minutes and 6-hours of exposure to 2% chlorhexidine and 2% glutaraldehyde do not cause a significant change in the surface roughness of heat cure acrylic resin whereas 10-minutes and 6-hours of exposure to 2% sodium hypochlorite and novel solution cause a significant change in the surface roughness of heat cure acrylic resin.