In the present study, the synergistic effect of non-electrolytic hypochlorite water (NEHW, 50 mg/L, pH, 5.8) immersion combined with ultrasonic treatment (US, 32 kHz) on the inactivation of bacteria and the maintenance of quality in baby cabbage (Brassica pekinensis) was evaluated. Baby cabbage was treated with tap water immersion, tap water immersion combined with ultrasonic treatment, NEHW immersion combined with ultrasonic treatment and nontreatment (as the control group), and be stored at 4 °C. The results showed that NEHW immersion combined with ultrasonic treatment improved the sensory freshness of baby cabbage, slowed down the rise of weight loss rate and relative conductivity, reduced the number of natural bacteria, yeast and mold, inhibited the rise of nitrate and nitrite content and inhibited the loss of Vitamin C (VC), total phenol and soluble sugar. It is suggested that the shelf life of baby cabbage can be effectively extended with the treatment of NEHW immersion combined with ultrasonic.