Gene escape and fruit quality characteristics of transgenic melons (Cucumis melo L. var inodorus cv. 'Kirkagac 637') resistant to zucchini yellow mosaic virus (ZYMV) and control plants were investigated under screenhouse conditions. No significant differences were observed between transgenic and transgenic × control genotypes, with regard to rind thickness, fruit cavity length, fruit cavity width, total soluble solids, pistil scar diameter, and peduncle length. Fruit characters, including fruit weight, fruit width, fruit length, fruit flesh thickness, and peduncle diameter were significantly different. These results indicate that transgenic × control genotypes had higher values than transgenic (T4 and T20) genotypes, regarding fruit weight, fruit width, fruit length, fruit flesh thickness, and peduncle diameter. Significant differences were not observed between transgenic (T4 and T20), control, and transgenic × control genotypes in terms of L-ascorbic acid, malic acid, citric acid, sucrose, glucose, or fructose, but differences were observed for fruit total acidity. Esters, lactones, and alcohols were aroma components, but none differed significantly between the transgenic and control genotypes. The results show that there was 100% gene escape in the control plants within 10 m of the transgenic plants, while there was 70% gene escape in plants 12.5, 15, and 17.5 m from the transgenic plants under screenhouse conditions.