In this research, the effects of postharvest 1-methylcyclopropene (1-MCP) treatments on fruit quality of 'Esme' quince cultivar during storage were evaluated. For this purpose, fruits harvested from Canakkale-Kepez province were treated with 1-MCP (Smartfresh (TM)) with 625 and 1250 ppb doses for 24 hours and were stored in plastic boxes at 0-1 degrees C temperature and 85-90% relative humidity for 2, 4 and 6 months respectively. After each storage period, fruits were kept at 18-22 degrees C for 7 days as shelf life. After harvest and each storage period with shelf life, some quality parameters as skin color, weight loss, fruit firmness and total soluble solids were measured. Also the rates of internal browning were calculated. Furthermore, some biochemical properties as titratable acidity were evaluated. Based on the results, most of the quality parameters and biochemical properties were affected positively by 1-MCP (Smartfresh (TM)) applications during the storage periods. Thus 1-methylcyclopropane applications were found effective at decreasing the rate of internal browning in quince fruits.