The inhibitory activity of eugenol was evaluated on Providence vermicola, which is a strain isolated from spoiled spicy crab product. The results showed that the minimum inhibitory concentration (MIC) was 0.25 mg/mL. Compared with the control group, the cells of P. vermicola treated with MIC eugenol were severely deformed, and wrinkles appeared. The cell wall of P. vermicola treated with eugenol was destroyed, leading to the leakage of intracellular substances and higher extracellular soluble protein content. The enzyme activities of malic acid dehydrogenase (MDH) and succinate dehydrogenase (SDH) were reduced by 33.01% and 19.81%, respectively. The normal metabolic system of bacteria is dysfunctional, and thus inhibit the growth and reproduction of P. vermicola.