One of the prominent types of connective tissue cells is fibroblast that synthesizes and maintains the extracellular matrix of many animal tissues. Previous studies illustrated that calprotectin protein has different cytotoxicity effects on fibroblast cells. Calprotectin is abundant in the neutrophil cytosol; it has growth-inhibitory and apoptosis-inducing activities against various cell types such as tumor cells. The present study tries to introduce mechanism of growth inhibitory effect of calprotectin on human foreskin fibroblast cells (HFFF) and compare to etoposide (chemotherapy agent as control). Calprotectin was purified from human neutrophil by chromatography methods. HFFF cell lines were used, maintained in RPMI 1640 medium supplemented with 10% FCS in a humidified incubator (37 ºC & 5% CO2). The HFFF cells were exposed to the different concentrations of calprotectin and etoposide for 24, 48 and 72 hours. Cell proliferation was assessed by using dimethylthiazol diphenyl tetrazolium bromide assay. Flow cytometric analysis was performed to evaluate the cytotoxic mechanism of calprotectin on HFFF cells. Our results revealed that calprotectin and etoposide induce growth inhibition of HFFF in dose- and time-dependent manners. Sensitivity of HFFF cells to cytotoxic effect of human calprotectin was highly remarkable. In addition, growth inhibitory effect of this cytotoxic agent mostly was governed through induction of apoptosis in the HFFF cells. Taken together, calprotectin not only has more potent anticancer activity in comparison with the etoposide, but it also is an apoptosis inducer that acts on the proliferation of normal cells like fibroblasts.