A prerequisite for a successful placement of cabbage on the market are healthy cabbage heads. Plant disease agents and pests present a problem, as they damage them making them inadequate for the market. The most important problem in cabbage protection in the area of Knin in the recent years have been flea beetles (Phyllotreta spp.) and diamondback moth (Plutella xylostella L.). A test of insecticide effectiveness from different chemical groups in control of the most important cabbage pests was conducted from July to September 2018. The test was performed on the cabbage in the municipality of Biskupija, in Šibenik-Knin County. The research included three insecticides from different chemical groups: imidacloprid (neonicotinoid), dimethoate (organic phosphate insecticide) and alfa-cypermethrin (pyrethroid). Upon reading the results, 10 plants were visually inspected in each plot of land. The total number of leaves was recorded on each inspected plant, as well as the number or percentage of damaged leaves. Upon the completion of vegetation, the results of the weighing of cabbage heads were released during all the test versions. The insecticide “Rogor 40” (dimethoate) from the group of organic phosphate insecticides showed a significantly higher effectiveness both after the first and the second treatment compared with the insecticide “Boxer 200 SL” (imidacloprid) from the group of neonicotinoids and with the insecticide “Fastac 10 EC” (alpha-cypermethrin) from the group of pyrethroids. The average head size was significantly larger in plants treated with “Rogor 40” (dimethoate), as opposed to other variants in the test.