In this study, the changes in color, ascorbic acid, antioxidant activity and phenolic compounds of raspberry and blackberry cultivars after marmalade processing were evaluated. For this purpose, raspberry fruits (Rubus idaeus L.) of four cultivars (Aksu Kirmizisi, Rubin, Hollanda Boduru and Heritage) and blackberry fruits (Rubus fruticosus L.) of three cultivars (Bursa 1, Bursa 2 and Chester) were used. According to the results, color values of blackberry cultivars and marmalades were lower than the color values of raspberry. Raspberry cultivars were more durable to thermal processing than blackberry cultivars in terms of ascorbic acid degradation. An 84.19% decrease was seen in the antioxidant activity of raspberry and blackberry cultivars after marmalade processing. The marmalade produced from Hollanda Boduru had the highest antioxidant activity. Ellagic acid was predominant in all raspberry and blackberry cultivars and ranged from 727.90 +/- 9.21 mg/kg (Rubin) to 1,828.07 +/- 23.73 mg/kg (Chester). None of the phenolics was determined in marmalades.