Abstract: The effects of 1-methylcyclopropene (1-MCP) on chlorophyll content, ethylene production and endogenous hormones of postharvest broccoli (Brassica olracea L. var. italica) were investigated. Results showed that the degradation of chlorophyll in florets was delayed, and the sensitivity of broccoli to ethylene was reduced by 1-MCP treatments. 1-MCP could also delay the degradation of GA and the accumulation of ABA. The ratio of ABA/GA and ABA/IAA of broccoli after 1-MCP treatment increased slowly.