The search for environmentally friendly alternatives to synthetic pesticides has led to increasing interest in plant-derived insecticides. This study evaluated the insecticidal activity of leaf extracts from Philippine cherry against the fall armyworm, Spodoptera frugiperda, a destructive pest affecting major crops. Leaves were collected, dried, and extracted using methanol through maceration. Preliminary phytochemical screening was conducted to identify bioactive compounds. Bioassays were performed using different concentrations of the extract against third instar larvae of S. frugiperda. Mortality rates were recorded after 24 and 48 hours. Results indicated that the extract exhibited dose-dependent insecticidal activity. Phytochemical analysis revealed the presence of flavonoids, alkaloids, tannins, and phenolic compounds which may contribute to insect toxicity. Statistical analysis using ANOVA showed significant differences among treatments (p < 0.05). The findings suggest that S. lineatum leaf extract has potential as a botanical insecticide.