Broccoli (Brassica oleracea L.) is rapidly perishable because of the loss of green color and the consequent yellowing of florets after harvest at ambient temperature. Therefore, the purpose of the study was to investigate the effects of melatonin (MT) solutions at 75, 100 and 125 μM and ascorbic acid (AA) solution at 0.5, 1 and 1.5% in addition to control on delay of senescence and quality attributes, and shelf life extending of fresh broccoli florets after harvest and during cold storage at 5˚C and 90-95% relative humidity for 16 days, during two successive seasons of 2024 and 2025. The obtained results revealed that the application of melatonin at 100 μM was notably effective in reducing weight loss. Moreover, giving a good general appearance (score) and retention of green color (high hue angle), maintained lightness after 16 days at 5°C and as well as maintained the total content of chlorophyll, photonic content and vitamin C. Whereas, ascorbic acid treatments were less effective in this concern in two tested seasons.