Paullinia pinnta leaves are known for many medicinal properties. This study was undertaken to evaluate the antihypertensive activity of the aqueous and ethanolic extract of the leaves of Paullinia pinnata on an anaesthetized normotensive cat. Both extracts of P. pinnata leaves produced positive results for alkaloids, tannins, flavonoids, saponins, phenols, cardiac glycosides, terpenoids and steroids to the same extent in terms of concentration. The antihypertensive study involved the administration of equal volumes of varying concentrations of the aqueous and ethanolic extracts of P. pinnata leaves to the anaesthetized normotensive cat. The incremental concentration of both the ethanolic and aqueous extracts of P. pinnata leaves showed a positive ionotropic effect in the anaesthetized normotensive cat and is dose dependent and may involve any adrenergic receptor mediated action. The percentage reduction of the mean arterial blood pressures caused by the aqueous and ethanolic extracts are 0%, 11.86%, 0.13%, 6.52% and 5.66%, 0%, 14.82%, 47.17% respectively. One sample t test analysis with a test value of 100 gave mean values of (4.62 ± 2.85) and (16.91 ± 10.54) for aqueous extract and ethanolic extract respectively. This indicates that the ethanolic extract worked more effectively than the aqueous extract. This indicates that the ethanolic extract worked more effectively than the aqueous extract; and may be due to the presence of bioactive compounds which are of therapeutically potent antihypertensive agents. These findings show the potential antihypertensive activity of P. pinnata leaves to be use in treating or managing hypertension.