Slightly acidic electrolyzed water (SAEW), an efficient non-thermal microbial inactivation technique, has been broadly applied to control food safety and quality. This study aimed to evaluate the bactericidal effects of SAEW treatments on fresh cut cabbage and to assess the optimal treatment conditions for inactivating Pectobacterium carotovorum subsp. carotovorum (PCC), which is among the most common causes of soft rot in cabbage. To this end, multivariate statistical analysis was performed using response surface methodology (RSM) based on the Box–Behnken design (BBD) technique. The optimal treatment condition for disinfection of PCC with SAEW treatment comprised 22.17 ppm of free available chlorine in the SAEW and an exposure time of 180 s at 10 °C. The optimized SAEW treatment was verified experimentally on fresh cabbage with an observed reduction value of 5.94 ± 0.07 log10 CFU/g, which was similar to the predicted reduction value (6.21 log10 CFU/mL) in the suspension test. Taken together, these results indicate that SAEW can efficiently inactivate PCC cells in fresh cut cabbage. Moreover, the response surface quadratic polynomial equation is applicable for predicting the effect of SAEW treatments on PCC contamination in fresh cabbage production, processing, and distribution.