Casearia grewiifolia Vent. is a medicinal plant of which its leaf has been historically utilized as a medicinal herb in Thai traditional pharmacopeia. This research aimed to investigate the bioactivities related to skin inflammatory conditions of ethanolic extracts of C. grewiifolia leaf. The extracts namely C40, C70, and C95 were obtained by maceration with 40%v/v, 70%v/v, and 95%v/v ethanol, respectively and then dried through lyophylization. The antioxidant capabilities of the extracts were then determined by means of three different methods, namely DPPH, ABTS, and Nitric Oxide (NO) radical scavenging assays. The antibacterial activities against Staphylococcus aureus and Escherichia coli were also tested by a disc diffusion method. Additionally, total phenolic and flavonoid contents of the extracts were determined. The results showed that the ethanolic concentration of the extracting solvents had an important influence on the bioactivities of the extracts. The C70 was shown to have the highest antioxidant potential among all extracts. Moreover, C70 was the only condition which displayed an inhibitory effect on both S. aureus (4.73±0.60 mm) and E. coli (9.71 ± 6.40 mm). On the contrary, C40 only inhibited E. coli while C95 displayed the least bioactivity in all antioxidant assays and did not display any inhibitory effects towards either bacterial species. In addition, the result of phytochemical profile of C70 displayed 557.24±69.39 mgGAE/g extract and 566.56±55.31 mgQE/g extract for total phenolic and flavonoid contents, respectively which is the highest among all extracts. In conclusion, 70% ethanol is therefore considered to be the best extraction condition for isolating bioactive compounds from C. grewiifolia. In addition, due to their outstanding antioxidant capabilities and their wide spectrum of action toward skin pathogenic microorganisms, our findings offer strong scientific support for its possible application as an active ingredient in pharmaceutical preparations or cosmeceutical product.