Introduction: Lead exposure has a negative impact on health. Lead can caused abnormality hematologic parameters. Orthosiphon stamineus Benth is one of the herbal medicines and known to have antioxidant, anti-inflammatory, and anti-angiogenesis.

Objective: This study aims to prove the effect of Orthosiphon stamineus Benth on hematologic parameters in lead acetate induced Wistar rat.

Method: The study used posttest only control group design. The samples were 30 male Wistar rats, divided into 5 groups. Normal control group (NC) was given normal saline. Negative control group (NG) was induced by lead acetate 30 mg/kg/day. GT-50, GT-100, GT-200 was induced by lead acetate and orally administered by 50,100, and 200 mg/kg Orthosiphon extract once daily for 14 days respectively. One-way Anova and post hoc LSD were used for statistical analysis.

Result: Hemoglobin level and leukocyte count in all group were not different (p=0.56 and p=0.25). There was a significant difference in platelet count between all group (p=0.035). Platelet count in NC group (900 ±171 x103/μl) was significantly higher than NG group (656±201 x103/μl, p=0.016), NG group was significantly lower than GT-50 (869±134 x103/μl, p=0.032), GT-100 (930±162 x103/μl, p=0.008) and GT-200 (938±148 x103/μl, p=0.006)

Conclusion: There is a decrement of platelets number in lead acetate exposure. Orthosiphon stamineus Benth may increase platelet counts in lead acetate induced Wistar rat.

Keywords: Orthosiphon stamineus Benth, hemoglobin, leukocytes, platelets