Objective: This study aimed to observe the effect of the 70% ethanol extract of Orthosiphonis stamineus Benth leaves on the pharmacokinetic parameters of furosemide in white male rats.Methods: 18 Sprague-Dawley male rats were divided into three groups: The normal control group was given only 1% carboxymethyl cellulose, the furosemide group was given 7.2 mg/200 g body weight (BW) suspension of furosemide, and the combination group was given 700 mg/kg BW suspension of the 70% ethanolic extract of O. stamineus Benth leaves for 4 days followed by a 7.2 mg/200 g BW suspension of furosemide. On the 4 th day of treatment, we performed orbital sinus blood sampling on the eyes of the rats and analyzed the levels of furosemide in plasma using highperformance liquid chromatography.Results: Therefore, the results showed that the administration of the 70% ethanol extract of O. stamineus Benth leaves improves the pharmacokinetic parameters of furosemide on Cp max and the area under the curve (p<0.05). Conclusion:This study concludes that the 70% ethanol extract of O. stamineus Benth leaves improves the pharmacokinetic parameters of furosemide in white male rats.