Plant botanical extracts are recognized for being a source of biologically active phytochemicals that potentially have diverse applications. The phytochemical composition, potential cytotoxicity, and insecticidal effectiveness of three leaf extracts from the folkloric medicinal plant Mammea americana L. (Calophyllaceae) were investigated. Micro-Soxhlet extraction with chloroform, dichloromethane, and methanol was used, and key phytochemicals were identified via Gas Chromatography-Mass Spectrometry (GC-MS). The extracts were mainly composed of sesquiterpenes, carboxylic acids, coumarins, esters, diterpenes, and other bioactive compounds. Potential cytotoxicity was assessed using brine shrimp lethality tests, where all extracts displayed high toxicity to Artemia salina. The dichloromethane extract (MAD) had the lowest LC50 value (8.39 μg/mL), followed by methanol extract (MAM, 11.66 μg/mL) and chloroform extract (MAC, 12.67 μg/mL). Insecticidal activity was tested against Ferrisia sp. (Hemiptera:Pseudococcidae), demonstrating the highest efficacy with the methanolic extract (LC50 = 5.90 mg/mL after 48 h). These findings provide a basis for further research into the bioactive components of Mammea americana leaves, particularly their antibacterial, anti-inflammatory, and anticancer properties. It also highlights the potential of Mammea americana L. leaf extracts as botanical insecticides due to their high bioactivity against agricultural pests of economic significance. This is the first study that evaluates the insecticidal activity of Mammea americana leaf extracts against Ferrisia sp. insects, offering valuable insights into using plant-based natural products in pest control.