Basil (Ocimum basilicum L.) is rich in phenolic compounds with various bioactivities, which makes it a potential cosmeceutical ingredient. This study aimed to investigate the bioactivities of O. basilicum L. water extract (OBWE) for its application in anti-acne cosmeceutical. To improve the content of antioxidants, the extraction condition was optimized as follows: 1:20 g/mL of material-to-solvent, 1 h of extraction time at temperature of 90 ℃. Liquid chromatography-mass spectrometry (LC-MS) and gas chromatography-mass spectrometry (GC-MS) analysis of OBWE identified 931 and 370 metabolites, including bioactive compounds like rosmarinic acid, caffeic acid, linalool and eugenol. The extract exhibited strong free radical scavenging activities. The inhibition zone of OBWE to Cutibacterium (C.) acnes was 18.71 mm diameter, which was significantly larger than 10.87 mm of 0.1 % salicylic acid. Moreover, treatment with OBWE significantly suppressed lipopolysaccharide (LPS)-induced accumulations of pro-inflammatory cytokines (tumor necrosis factor-α, interleukin 6, interleukin 1-β) in THP-1 macrophages. Thus, OBWE showed a two-fold benefit for acne treatment by inhibiting proliferation of C. acnes and suppressing the bacterial-induced inflammation. In summary, our results suggest OBWE as a natural product with potential anti-acne effects. • Extraction condition for Ocimum basilicum L. water extract (OBWE) was optimized. • The phytochemical composition of OBWE was evaluated by LC-MS and GC-MS. • OBWE displayed strong antibacterial activity towards Cutibacterium acnes. • OBWE treatment alleviates the LPS-induced accumulation of pro-inflammatory cytokines. • OBWE has great potential for the anti-acne cosmeceutical application. [ABSTRACT FROM AUTHOR]