DLBS3233 is a standardized extract combination of two Indonesian herbals (Lagerstroemia speciosa L. and Cinnamomum burmanii L.) developed by a patented extraction-technology. DLBS3233 has been proven pre-clinically to have a glucose lowering activity. This Phase 1 clinical study evaluated the safety of DLBS3233 in comparison with the negative-control and pioglitazone 30 mg (active control) in healthy volunteers. In this randomized, open-labeled, Latin-square-designed clinical study consisting of 7 groups of treatment, DLBS3233 capsules were given at doses of 50, 100, 200, 300, 400 mg in each group, respectively. The Active Control group received pioglitazone 30 mg and the Negative Control did not receive any study drug. All study drugs were administered once daily for three days prior to the conduct of 75 g glucose oral loading at each study course. Wash-out period between each course was one week. Safety parameters were blood glucose profile, liver and renal functions, and adverse events. Six healthy volunteers with a mean age of 27.8 ± 6.1 years old were enrolled in the study. The result demonstrated comparable blood glucose profiles between all groups indicating that both DLBS3233 and pioglitazone do not exert a hypoglycemic effect in non-obese healthy subjects with normoglycemia. DLBS3233 treatment did not affect liver and kidney function. Neither did it cause any serious adverse events. Overall, this study demonstrated the low risk of DLBS3233 to induce hypoglycemia and that the extract was safe and well tolerated.