Nitric oxide (NO) is a gaseous free radical that has been become a potential tool to maintain the quality of postharvest horticultural produce. It plays important roles in delaying ripening, alleviating chilling injury, preventing browning, and enhancing disease resistance. The regulatory function of NO is achieved through the post-transcriptional modification of proteins, such as tyrosine nitration, S-nitrosylation, and nitroalkylation. Secondly, NO can also induce the expression of stress-related genes by synergistically interacting with other signaling substances, such as Ca²⁺, ethylene (ETH), salicylic acid (SA), and jasmonic acid (JA). Here, research progress on the role of NO and its donors in regulating the quality of postharvest fruits and vegetables under storage is reviewed. The function of NO crosstalk with other phytohormones is summarized. Future research directions for NO commercial application and the endogenous NO regulatory mechanism are also discussed.