Although ecological roofs (vegetated or non-vegetated) provide many bene ts, it can also leach substances such as nutrients and metals that can affect downstream aquatic ecosystems. Recife has a legislation requiring the installation of green roofs under certain conditions. Therefore, this work aims to investigate the rainwater quality from ecological roofs in Recife using local species in a tropical and humid climate. Using four test cells of 1m² (one non-vegetated lled with expanded clay aggregate, two vegetated with cactus "Coroa-de-Frade" and grass "Grama Esmeralda", and one control roof) we analyzed thirteen water quality variables regarding irrigation parameters: pH, electrical conductivity, turbidity, nitrate, ammonia, phosphate, bicarbonate, carbonate, calcium, magnesium, sulfate, potassium, boron, sodium, and sodium adsorption ratio. We simulated rain events controlling its intensity and analyzed a sample of natural rainwater event. All roofs neutralized the pH. Control and clay roofs were source of bicarbonate and calcium, responsible for more alkaline e uents. Carbonate and ammonia were below the recommended limits for irrigation purposes for all roofs. Green roofs were source of NO3-, NH4 + and B-. All roofs were neither source or sink for sulphate and chloride for all analyzed samples. Regarding the natural rainwater experiment, only green roof with Coroa-de-Frade exceeded the recommend irrigation parameters for potassium and phosphate. A post-treatment is required for irrigation purposes being recommended a rst-ush system followed by a lter with sand and activated carbon.