Insecticidal effect of methanol and ethyl acetate leaves extract of Sida acuta were studied against Dysdercus cingulatus. The plant leaves were dried, powdered and extracted in soxhlet apparatus in methanol and ethyl acetate solvent for 24 hrs. The adult red cotton bug, D. cingulatus were exposed to various concentration and percent mortality were recorded after 96hrs. The insecticidal activity of leaves extract of Sida acuta were LD₁₀= 3.741μg/gm. LD₅₀= 9.690μg/gm., LD₉₀=13.38μg/gm., LD₉₉= 14.15μg/gm. in methanol and LD₁₀₌ 2.671μg/gm., LD₅₀= 6.165μg/gm., LD₉₀= 13.25μg/gm., LD₉₉ = 14.32μg/mg. in ethyl acetate. Results revealed that the mortality increase with increase in concentration of the plant extract. The ethyl acetate solvent extract showed more insecticidal property against Dysdercus cingulatus. Stastical variance, 95% confidance limits and regression equations are presented.