Water hyacinth (Eichhornia crassipes) is a rapidly proliferating, invasive aquatic species that serves as a potential biomass resource for bioenergy generation and may be utilised as a biopesticide. The main objective of the study, was to evaluate the effectiveness of water hyacinth (Eichhornia crassipes) extract against the termites (Odontotermes obesus). Fresh leaves of E. crassipes were gathered from the River Niger region in Niger State and evaluated for the phytochemical parameters, termite mortality, and the repellency of the plant extract against termites. The findings indicated the existence of saponins, tannins, flavonoids, glycosides, and anthraquinone. The leaf extract of water hyacinth induced mortality rates of 33.3%, 46.7%, and 60% in termites at concentrations of 1%, 2%, and 3% g/ml, respectively, after 6 hours of treatment. The leaf extract demonstrated 80%, 86.7%, and 100% mortality rates of termites at concentrations of 1%, 2%, and 3% g/ml, respectively, following an 18-hour treatment period. No significant difference (p>0.005) was seen between the 3% concentration of the extract and the standard control after 18 hours of treatment. The leaf extract of water hyacinth exhibited average percentage repellency against termites of 23.3%, 33.3%, and 36.7% at doses of 1%, 2%, and 3% g/ml, respectively. All concentrations of the extract exhibited class II repellency. The leaf extract of water hyacinth is advised for termite management in the environment as an alternative to synthetic insecticides.