Aims: The purpose of this study was to determine the diuretic and electrolyte excretion properties of the aqueous extract of Celosia trigyna L. (Amaranthaceae) on female Wistar rats. Methodology: The extraction of active principles was done by macerating aerial parts of the plant. The administration of the extract and other products was done by single-dose gavage. Measurements of urinary flow rate (UFR), natriuria, kaliuria and chloruria were taken on urine collected for twenty-four hours after each product was administered. Diuretic activity (DA) and diuretic index (DI), natriuretic and saluretic effects, and carbonic anhydrase inhibition were calculated. A NaCl solution (0.9%) was used as a negative control; furosemide and aldactone were respectively used as hypokalemic and hyperkalemic positive controls. Results: We observed a significant increase in UFR, confirmed by the values of DA and DI, obtained after the administration of extract. For electrolyte excretion, we observed an increase of the kaliuria (p ˂ 0.001) and a decrease of natriuria (p ˂ 0.001) after the extract was administered; chloruria did not significantly changed. We also found a drastic anti-natriuretic dose-dependent effect while saluretic activity and carbonic anhydrase inhibition were not clearly observable. Conclusion: These results confirm the ethnobotanical data about diuretic effect of Celosia trigyna L. extract. This diuretic effect would be supported by a specific increase in K+ excretion suggesting that the extract is possibly hypokalemic. The anti-natriuretic effect suggests that extract possess an aldosterone-like properties.