Heliothis armigera and Spodoptera litura are two main economically important, plyphagous pests. They feed on wide range of crops. They are major pest of tobacco, tomato, cauliflower, peas, maize, brinjal, groundnut, soya bean and cotton etc. They affected the quantitative and qualitative fruit production in more than 157 plant species. Damage is caused in larval stage. Larva bore deeply in the fruit and caused severe damage. In the present study, efficacy of Cassia occidentalis was evaluated in the laboratory against the third instar larva of Heliothis armigera and Spodoptera litura. Toxicity was assessed with topical application method. Leaf and seed powder of plant get evaluated in this experiment. Extract of C. occidentalis used in three different doses i.e. 5gm, 10gm and 15 gm. Results indicated that percentage of larval mortality was directly related to the dose of powder. 15 gm dose of Kasaundi leaf and seed powder was proved to be most effective against both pests. 15 gm dose of treatment caused 76% mortality in Heliothis armigera after 20^th day of treatment. Similarly, highest larval mortality (77%) in Spodoptera litura recoded after 20^th day of 15 gm dose treatment.