Although experimental studies in vitro and vivo have been numerous, the effects of laser irradiation on human fibroblast cells are poorly understood. The aim of this study was to assess the influence on three different laser wavelengths on nanoparticles components of the human fibroblast cells from oral tumor. The cells were irradiated by 830, 920, and 2940nm laser wavelength. The irradiated cells were incubated and their mitochondrial activity was assessed by the MTT assay at 24, 48, and 72h. It can be concluded that the laser light with 830nm wavelength stimulates mitochondrial activity compared to the other two wavelengths, which produce inhibition.