A denture is a prosthetic rehabilitation device to replace missing teeth and supporting tissue of the oral cavity. However, its mechanical strength is still a problem that needs to be improved. Adding reinforcement material to the resin acrylic was considered one of the most effective ways. Polyacrylonitrile-Polymethyl Methacrylate (PAN-PMMA) electrospinning nanofibers are chosen because they have strength, large surface area, and are relatively easy to fabricate. This study presents a preliminary investigation into the reinforcement properties of heat-cured acrylic resin for denture applications. PAN-PMMA electrospinning nanofibers and commercial acrylic resin were formulated at a ratio of 0 wt %, 0.1wt %, and 0.5 wt %. The samples were characterized by X-ray Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR), and Scanning Electron Microscope (SEM). Mechanical properties testing was carried out using three bending point tests, whereas biocompatibility testing was carried out using 3T3NIH fibroblast cell cytotoxicity tests. XRD and SEM showed similar patterns. FTIR of samples with PAN-PMMA nanofibers showed a new band stretch which indicates the methyl group attached to acetonitrile band CH3_C = N functional group of nanofiber. The nanofibers biomaterial used in this study demonstrated a non-toxic nature as it showed a viability of more than 90% in all groups. In conclusion, formulated PAN-PMMA electrospinning nanofibers in the acrylic resin at the range of 0.1% - 0.5% did not affect the mechanical properties of resin and biocompatibility of 3T3NIH fibroblast cells.