The Red Pumpkin Beetle (RPB), Aulacophora foveicollis, is a major pest of summer squash and other cucurbit crops and causes significant damage. The pest appeared equally in both the glasshouse and open-field summer squash. This study was conducted under open field conditions to evaluate the efficacy of various insecticides against RPB using one of the registered hybrid varieties of summer squash, ‘Anna 303’ F1, in the subtropical region of Sindhuli from February to July 2023. A Randomized Complete Block Design (RCBD) was employed with five treatments that were replicated four times. The treatments significantly affected had a significant impact the insect population per plant, diameter, and fruit yield. All tested treatments significantly reduced the insect population per plant, consequently increasing yield per hectare. The results showed that the first, second, and third sprays of chlorpyriphos 50% + cypermethrin 5% EC resulted in 89.92%, 84.66%, and 82.35% mortality of RPB, respectively. The fourth spray of Spinosad (45% EC) resulted in 50% mortality of the pest. The highest yield was obtained from the Chlorpyriphos 50% + Cypermethrin 5.0% EC treatment with 30.94 mt ha-1, fruit length, and diameter of 36.12 cm and 5.47 cm, respectively. In contrast, the lowest yield was recorded in the control group, with 13.07 mt ha-1, and fruit length and diameter of 26.04 cm and 3.87 cm, respectively. Among these treatments, a spray of Chlorpyriphos (50%) + Cypermethrin (5.0% EC) is a potential insecticide for controlling RPB.