Introduction . Dengue fever has been known for more than two decades as a tropical endemic infection caused by the dengue virus that affected from Aedes aegypti . Complications of dengue fever are common and usually related to renal and hepatic dysfunction. Encephalopathy is a rare complication. Here we report an unusual case of pregnant woman with dengue encephalopathy. Results . A 28-year-old female, G1P0A0, consulted by the anesthetic division with loss of consciousness. Prior to that, she had acute fever with history of acute progressive cephalgia and positive results of IgG and IgM dengue antibody. She was 20 weeks of pregnancy. On examination she was stuporous (E2V2M5). Lateralization, pathological reflex, and meningeal signs were not found. Laboratory examination showed thrombocytopenia 23 × 10 3 /µl, increased transaminase enzyme, hypokalemia 2.53 mmol/L, and hypoalbuminemia 2.35 gr/dL. Head CT Scan showed cerebral edema. During hospital care, she was monitored closely. Careful fluid management was carried out with additional treatment consisted of thiamine 100 mg/12 h, piracetam 800 mg/12 h, folic acid 2 × 1 mg, and transfusion of albumin and premix KCL. Patient condition was improved after 7 days of hospital care. The encephalopathy lasted for 5 days. Patient was discharged with full of consciousness and the baby was safe. Conclusion . Encephalopathy is a rare manifestation of DHF. However, it is a significant diagnostic challenge when it presents in atypical form, especially during pregnancy. It was first reported in 1976, and worldwide literature search shows the various incidence of dengue encephalopathy from 0.5% to 6.2% with a mortality rate up to 40%. The complications of dengue in pregnancy have been scarcely studied. There are increased risks of maternal hemorrhage, preterm labor and stillbirths. Dengue should be the differential diagnosis even a pregnant women presents with fever and altered sensorium especially in endemic areas like Indonesia.