In this research, the effects of rootstocks on the storage performance of Nova mandarins grafted on Carrizo citrange, Troyer citrange, or sour orange grown in the ecological conditions of Dörtyol were studied. Fruits were harvested at optimum maturity and kept at 4 °C and 6 °C for 120 days. Changes in weight loss, incidence of fungal decay and physiological disorders, juice content, total soluble solids (TSS), percent fruit with green button, titratable acidity (TA), juice pH, vitamin C content, and rind color (L*, C*, h°) were monitored at 15-day intervals during storage to determine the effects of rootstock on postharvest quality of Nova mandarins. The fruit of Nova mandarin grafted on sour orange and Carrizo citrange had higher weight loss than Troyer citrange. Weight loss from Nova mandarins kept at 4 °C and 6 °C reached 7.71% and 12.21%, respectively, after 120 days of storage. Juice pH, incidence of fungal decay, and physiological disorders increased, while juice content, TA, vitamin C content, percent fruit with green button, and L*, C*, and h° values of rind color decreased in the Nova mandarin cultivar during cold storage. According to the data, the fruits of Nova mandarin grafted on Carrizo citrange, Troyer citrange, or sour orange were stored better at 4 °C than 6 °C. Fruit could be kept at 4 °C for 75 days and at 6 °C for 45 days without any quality deterioration.