The objective of this study was to determine the effects of 1-MCP on quality of 'Fuji' apples during long-term storage. 'Fuji' apples were harvested at commercial mature stage, treated with 325 and 650 nl l(-1) of 1-methyleyclopropene (1-MCP) at 20 degrees C for 24 h and quality parameters were checked monthly, in comparison with control fruits during eight months of cold storage at 0 degrees C and 85-90% RH. Both 1-MCP doses suppressed internal ethylene concentration, reduced weight loss, delayed softening and maintained the acidity and total soluble solids compared to the control during eight months of storage. Results showed that both doses can be used to suppress ethylene and maintain quality during storage. However, 650 nl l(-1) may be more efficient under commercial conditions.