In this study, the effect of ultraviolet (UV) irradiation time, incubation time and callus age were investigated for resveratrol induction which is a stilbene compound, in callus cultures of 'Ercis' grape cultivar (Vitis vinifera L.). Callus tissues were obtained from the leaves of the cuttings grown in greenhouse. Gamborg B-5 media including 2% saccarose, 0.8% agar, 1.0 mu M BAP (6-benzylaminopurine) and 0.1 mu M 2, 4-D (2, 4dichlorophenoxy-acetic acid) was used as culture media. Callus tissues were sub cultured two times with 21 days intervals. After the second subculture, 12 and 15 days old callus tissues were exposed to 254 nm UV light at 10 cm distance from the source for 10 and 15 min by opening covers of the petri dishes in sterile cabin. After UV treatment, callus tissues were incubated at 25 degrees C and in dark conditions. High Pressure Liquid Chromatography (HPLC) was used for determining of resveratrol production and concentrations were recorded at 0, 24, 48 and 72 hours after beginning of incubation. The highest resveratrol concentration (66.39 mu g/g FW) was determined at 48 hours of 12 days-old callus cultures irradiated for 10 minutes. Generally, resveratrol accumulation in 12 days-old callus cultures was higher than that of 15 days-old. Both 10 min and 15 min UV irradiation periods were found to be effective for induction of resveratrol production and thus callus cultures could be convenient for resveratrol production.