Cotton bollworm, Helicoverpa armigera Hübner (Lepidoptera: Noctuidae), is one of the most important and key pests of cotton in Iran. This study was carried out with the aim of investigating the efficacy of several different insecticides on cotton bollworm in three regions of Golestan province, Iran, in a completely randomized design with 4 replications and 7 treatments. Experimental treatments include: Proclame-Fit® 150 g/ha, Profenofos® 2.5 lit/ha, Cypermethrin® 150 ml/ha, Indoxacarb® 250 ml/ha, Karvin® 1.5 lit/ha, Fenpropathrin® 1 lit/ha and control (water without insecticide). Samplings unite of cotton bollworm larvae was 10 cotton plants per plot which were recorded the number of immature pests per plant at the before spraying, 3, 7, and 14 days after spraying. The larval mortality of treatments was modified by the Henderson-Tilton formula to determine the efficiency percentage. According to the results obtained in Bandar-e Gaz, Proclame-Fit® and Karvin® had the highest long-term effect 50.85% and 59.86%, respectively, and Profenofos® had a suitable short-term effect with 74.82% mortality percentage. In Gonbad-e Kavous, Proclame-Fit®, Profenofos® and Karvin® with 96%, 94.33 % and 80% have shown a suitable lethal-short-term effect on cotton bollworm larvae. In Ramian, Proclame-Fit®, Profenofos ® and Karvin ® showed the highest short-term effect on cotton bollworm larvae, 83.18 %, 88.97 % and 88.37%, respectively. Based on the results, to control cotton bollworm, Proclame-Fit ® and Profenofos® are recommended as appropriate insecticides with the recommended doses.