For over 35 years now, residents of DBP Village in Ma-a, Davao City have been using the infusion of its leaves to relieve certain health conditions which manifest themselves in its most annoying symptom – edema. The study focused on the diuretic potential of the black zapote (Diospyros digyna Jacq., Ebenaceae) leaves when used as formulated tea. The use of Furosemide as the diuretic of choice in combination with other medications has triggered investigation into the possibility of using the tea from black zapote leaves, minus the side effect emanating from combination drugs. Tests on the toxicity and approximate effective dose (AED) of the formulated tea from black zapote leaves were done so that comparative analysis of its efficacy as a potential diuretic can be performed in relation to Furosemide as positive control and purified water as negative control. A total of 22 healthy, adult male and three nulliparous, non-pregnant female Swiss mice were used as test animals in the experimental stages. The tests showed urine output-increasing activity on Swiss mice using the formulated tea from leaves which compared significantly with the tested positive control – Furosemide. The tests using purified water as negative control in comparison with Furosemide and formulated tea from black zapote leaves proved otherwise. Thus, formulated tea from black zapote has a potential as a diuretic, disproving the null hypothesis that formulated tea from black zapote leaves has a potential as a diuretic.