Root-knot nematodes (Meloidogyne incognita) threaten banana production, and chemical controls pose environmental risks. Millettia pachyloba Drake contains bioactive compounds that can manage pests sustainably. This study investigates the nematicidal effects of M. pachyloba aqueous extract (EAMP) on M. incognita in Cavendish banana plants. Various EAMP concentrations (50, 100, 150, and 200 ppm) were tested for their effects on egg hatching, nematode mortality, enzyme activity, and plant health. The water control group showed no inhibition of egg hatching (0.00 ± 0.00%) (p < 0.05), while Oxamyl significantly reduced hatching to 13.11 ± 0.27% (p < 0.05). EAMP demonstrated a concentration-dependent reduction in egg hatching, with 200 ppm (EAMP200) showing the highest efficacy (23.13 ± 0.23%) (p < 0.05). Nematode mortality increased with concentration, with EAMP200 achieving a mortality rate of 71.74 ± 7.34% at 72 hours (p < 0.05). EAMP also reduced the root-knot index (RKI) and egg mass in a dose-dependent manner, with EAMP500 reducing RKI to 1.33 ± 0.58 and egg mass to 82.67 ± 2.08 (p < 0.05). Furthermore, EAMP treatments improved chlorophyll and carotenoid content in banana leaves, with EAMP500 showing the highest recovery (chlorophyll: 2.23 ± 0.04 mg/g, carotenoid: 0.18 ± 0.01 mg/g) (p < 0.05). These results suggest that EAMP is a promising, eco-friendly alternative for managing root-knot nematodes in banana cultivation.