B Background: matricaria chamomilla is a plant rich in flavonoids with antioxidant and anti-inflammatory activities. previous studies have shown that the extract exhibits antibacterial and antibiofilm properties and inhibits lipopolysaccharides and endotoxins from porphyromonas gingivalis. however, no safety evaluation of this extract on normal oral cavity cells is available. human gingival fibroblasts are the predominant cells in the gingival connective tissue and play a role in maintaining the normal structure and function of periodontal tissues. therefore, hgf, as normal cells in the gingival tissue, were used to assess cell viability after exposure to this ethanolic extract as an initial step in evaluating its safety and potential use in the context of periodontal disease. objective: to determine the effect of matricaria chamomilla ethanolic extract on the viability of human gingival fibroblasts. methods: this was an in vitro laboratory study that exposed hgf cultures to matricaria chamomilla ethanolic extract at concentrations of 10, 20, 40, and 1,000 μg/ml for 24 and 48 hours. cell viability was measured using the cell counting kit-8 assay. results: matricaria chamomilla ethanolic extract at concentrations of 10, 20, and 40 μg/ml maintained hgf viability at 96%, 97%, and 96% at 24 hours of incubation, and at 104%, 107%, and 111% at 48 hours of incubation. in contrast, the concentration of 1,000 μg/ml reduced viability to 28% (24 hours) and 20% (48 hours), which was significantly lower than that of the negative control (p ≤ 0.05). conclusion: matricaria chamomilla ethanolic extract at concentrations of 10–40 μg/ml is able to preserve hgf viability, whereas a concentration of 1,000 μg/ml decreases cell viability and indicates that this concentration has exceeded the tolerance threshold. these findings support the safety of lower concentrations for the development of periodontal therapeutic agents.