Atopic dermatitis increases susceptibility to Staphylococcus aureus colonization, while increasing antibiotic resistance underscores the need for alternative antibacterial agents. This study provides antimicrobial activity and synergistic potential of limonene and salicylic acid—two essential oil components commonly found in Indonesian plants—against S. aureus ATCC 25923. The antibacterial effect was measured using the inhibition zone diameter (IZD) and minimum inhibitory concentration (MIC) assays. Limonene produced the largest inhibition zone at a concentration of 400–500 mg/mL, while salicylic acid showed optimal inhibition at 100 mg/mL. The combination of the two with a 1:9 ratio produced the largest inhibition zone of 20.35 mm, with the volume ratio significantly affecting the IZD value (P < 0.001). The MIC results showed that limonene and salicylic acid had MIC values of 62.5 mg/mL and 6.25 mg/mL, respectively. The 1:9 combination substantially reduced the MIC to 0.12 mg/mL (0.01 mg/mL limonene and 0.11 mg/mL salicylic acid). A FICI value of 0.01 indicates a very strong synergistic effect (FICI ≤ 0.5). Overall, the combination of limonene and salicylic acid demonstrated significantly enhanced antibacterial activity compared to the individual compounds, supporting their potential as a synergistic alternative natural antibacterial for managing S. aureus-associated skin infections
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