This study aimed to evaluate the effects of variety and harvesting age on the physicochemical characteristics and nutritional composition of the fruits from three hybrid pumpkin varieties grown in Tra Vinh province of Vietnam. An increment in nutrient accumulation between 60 and 80 days old was observed in all three studied varieties. Adequate accumulation of dry matter, fat, fiber and ash in the fruit was achieved at 70 days old for the F1 pumpkin variety - long fruit (A1) while its maximum accumulation of protein and total phenolic content (TPC) was at 65 days old. A1 variety reached the highest total soluble solid (TSS) content at 75 days old. The F1 pea pumpkin variety (A2) had the highest accumulation of ash and fiber content at 60 days while the contents of fat, protein, carbohydrate and dry matter were maximal values at 65, 75, 70 and 70 days. The highest accumulation of fat, fiber, and carbohydrate was reached at 70 days old for the F1 hybrid pumpkin variety - round fruit (A3). The research results can be used to determine the appropriate harvesting age of the fruits to increase the value of the pumpkin varieties.