In a partial molar pregnancy, the level of β-Human chorionic gonadotropin (β-HCG) is often within a large spectrum. An extremely high level of β-HCG levels (>1.000.000) is only 2-3% of partial moles. Partial molar pregnancy commonly presented with mildly elevated HCG (<100,000), vaginal bleeding, abortion and rarely complicated with medical complications and theca lutein cysts. We present a case with extremely high HCG levels (1.861.011 IU / L) in the early second trimester and complicated by maternal anemia, hyperthyroidism, proteinuric hypertension, hirsutism, and enlarged bilateral theca lutein cysts. During follow-up, the patient's HCG level returned to normal after 27 weeks. Clinicians should keep in mind that partial mole hydatidiform may be presented with very high HCG levels. They should be aware of the medical conditions that may complicate this disease and adopt a multidisciplinary approach.Keywords: β, -Human chorionic gonadotropin (β-HCG), partial hydatidiform mole, theca lutein cysts, triploidy.