The purpose of our study was to establish the laser effects on the epithelial tissue and immune metabolism. The research was conducted on human leukemic mature T cells (Jurkat cells) (DSMZ-Deutshe Sammulung von Mikroorganismen und Zellkulturen (Germany)) and MDCK cell line (Lugar Laboratory, Tbilisi, Georgia). Cells were radiated by Laser device "ОПТОДАН"- АЛСТ-01 (power 5 W) 3 -7 days (4 minutes per day). With the aim to model oxidative stress-induced apoptosis, 30% hydrogen peroxide (H2O2) (Sigma) is added to Jurkat cells, in doses 25 and 50µM [4, 5]; and MDCK cells, in doses 400 and 800 µM [19] added to incubation suspension with subsequent incubation for 24, 48 and 72 hrs. Control group is represented by intact Jurkat and MDCK cells. MTT test was used to assess the cells' proliferation activity (viability). Statistical analyses of the obtained results were performed by SPSS (version 10.0) program package. Our research results show that effects of laser therapy on proliferation of cell cultures depend on the type of cells and incubation conditions. Laser irradiation revealed equal efficacy in both types of the intact cells and increased their viability in time-dependent manner. Jurkat cells turned out to be more susceptible to oxidative stress. Laser therapy only slightly improved their viability at moderate intensity of oxidative stress and proved to be ineffective in strong oxidative stress conditions. The MDCK cells appeared to be more sustainable to oxidative stress; significant changes in these cells viability were observed only when high doses of hydrogen peroxide were added to their incubation medium. Thus, laser therapy was effective for these cells incubated in both regimens of oxidative stress. Our research results prove the efficacy of laser therapy use during periodontitis with the aim to recover epithelium in the oral cavity and to modulate immune metabolism in the patient's body.