It is well reported that ultraviolet-C (UV-C) treatment enhances the storage or shelf life of many fruits and vegetables. However, biochemical changes associated with this treatment are largely unknown in leaf vegetables. The object of the present study is to evaluate the effects of UV-C treatment on the postharvest quality and biochemistry of three kinds of leaf vegetables (i.e. spinach, leek and cabbage). These vegetables were respectively exposed to single and multiple UV-C irradiations at the same energy level of 2.46 kJ/m2, and subsequently stored at 4 °C for 5 days. Total soluble protein, vitamin C and chlorophyll a were determined every day. As a result, the multiple UV-C treatment maintained significantly better quality parameters of postharvest leaf vegetables over the experiment, compared to the single treatment (p < 0.05). We therefore summarize that the multiple UV-C treatment can be an effective alternative to maintain the quality and to enhance the shelf life of postharvest leaf vegetables.