Antimicrobials agents at low concentration could stress out bacteria by inducing proteins production via regulating the transcription and translation process. The interruption of bacterial quorum sensing (QS), or cell-to-cell communication is known to have the potential to weaken the bacterial pathogenicity by inhibiting their communication. This study aims to explore the potential of synthetic antimicrobial compound, ethyl pentanoate in stimulating proteins production by Bacillus subtilis ATCC11774 as well as to determine the anti-QS activity of microbial proteins produced. The bacterial cells were exposed to 0.01 MIC of ethyl pentanoate in fermentation process at 37°C for 48 h and 72 h respectively. The proteins produced were further isolated and analyzed by using Sodium Dodecyl Sulfate-Polyacrylamide Gel Electrophoresis (SDS-PAGE). Results showed that a new extracellular protein with approximate size of 15 kDa was produced by B. subtilis ATCC11774 after being treated with ethyl pentanoate at 37°C for 48 h and 72h. Despites of new protein band production, there was a deletion of protein band with approximate size of 18 kDa on protein synthesized at 72 h of fermentation. Whilst, the anti-QS activity of microbial proteins produced by B. subtilis at 37°C for 48 h and 72 h was determined by agar- wells diffusion assay, resulting “halo” inhibition zone ranged from 10.00 ± 1.00 to 10.33 ± 0.56 in diameter. Therefore, B. subtilis ATCC11774 in the presence of ethyl pentanoate at 0.01 MIC could regulate the extracellular protein production and expression. The isolated protein also exhibited anti-QS activity.