Rosa hybrida L. cv. Lửa has been one of the most important roses for a long time and is most often used for ornamental purposes in Sa Dec city, Dong Thap province. The study aimed to research the effects of irradiation on in-vitro vegetative growth, propagation and ex-vitro hardening of the rose variety ‘Lửa’ for further improvement in rose breeding in Dong Thap province. In-vitro single node cuttings (25 in vitro cuttings per treatment with four replications) were irradiated with different doses of γ-rays (0, 5, 10, 15, 20, 25 or 30 Gy) using a 60Co source (India) at Da Lat Nuclear Research Institute. The γ-irradiated explants were then cultured aseptically on Murashige and Skoog‘s basal medium supplemented with 1.0 mg/L BAP to induce sprouting, shoot proliferation and acclimatization at Division of Vegetables, Flowers and Landscaping of Southern Horticultural Research Institute (SOFRI). The results showed that these doses affected the multiplication rate, growth in-vitro and ex-vitro survival rate. The LD50 dose was determined to be 20 - 25 Gy treatments. Explants treated at all doses showed deleterious effects of ionizing radiation but some plantlets at 15, 20 and 30 Gy were higher and stronger with large leaves than at the control.