The present study was carried out to understand the interaction between fibroblast and 3T3-L1 preadipocyte cells under H2O2-induced oxidative stress condition. H2O2 (40 mu M) was added in co-culture and monoculture of fibroblast and 3T3-L1 cell. The cells in the lower well were harvested for analysis and the process was carried out for both cells. The cell growth, oxidative stress markers, and antioxidant enzymes were analyzed. Additionally, the mRNA expressions of caspase-3 and caspase-7 were selected for analysis of apoptotic pathways and TNF-alpha and NF-kappa B were analyzed for inflammatory pathways. The adipogenic marker such as adiponectin and PPAR-gamma and collagen synthesis markers such as LOX and BMP-1 were analyzed in the co-culture of fibroblast and 3T3-L1 cells. Cell viability and antioxidant enzymes were significantly increased in the co-culture compared to the monoculture under stress condition. The apoptotic, inflammatory, adipogenic, and collagen-synthesized markers were significantly altered in H2O2-induced co-culture of fibroblast and 3T3-L1 cells when compared with the monoculture of H2O2-induced fibroblast and 3T3-L1 cells. In addition, the confocal microscopical investigation indicated that the co-culture of H2O2-induced 3T3-L1 and fibroblast cells increases collagen type I and type III expression. From our results, we suggested that co-culture of fat cell (3T3-L1) and fibroblast cells may influence/regulate each other and made the cells able to withstand against oxidative stress and aging. It is conceivable that the same mechanism might have been occurring from cell to cell while animals are stressed by various environmental conditions.