Objective To evaluate the hemodynamic changes and oxygen metabolism during whole body hyperthermia (WBH) therapy in patients with malignant tumor. Methods Twenty ASA Ⅰ - Ⅱ patients with advanced cancer aged 22-58 yr were enrolled in the study. The patients were premedicated with midazolam 0.05 mg ?kg-1 and scopolamine 0.3 mg im. Anesthesia was induced with intravenous droperidol 5 mg, fentanyl 100 ?g, propofol 2 mg?kg-1 and vecuronium 0.15 mg?kg-1 . The patients were mechanically ventilated after tracheal intubation (FiO2 = 100%, RR=10-12bpm, VT = 8-12 ml?kg-1 ) and fentanyl (2?g?kg-1 ? h-1 ), 1%-1.5% isoflurane inhalation and intermittent iv boluses of vecuronium and midazolam. Swan-ganz catheter was placed in the pulmonary artery for hemodynamic monitoring. Radial artery was cannulated for direct BP monitoring and arterial blood gas analysis. ECG and PaO2 were continuously monitored. Body temperature probes were placed in esophagus, rectum, naso-pharynx and body surface. Body temperature was warmed to 41.8t and maintained for 2 h. Stroke volume(SV), cardiac output(CO), mean pulmonary artery pressure (MPAP), vascular resistance index (SVRI), pulmonary vascular resistance index (PVRI), oxygen delivery (DO2), oxygen consumption (VO2) and oxygen extraction rate (O2ER) were calculated before warming (T0), at 39℃ ,40℃ ,41℃ , 41.8℃,41.8 ℃(1 h), 41.8℃(2 h) and when T0 was decreased to 40℃ and 38.5t (T1-8) .Results HR, CI, SI, CVP, MPAP and PCWP significantly increased with increasing body temperature, while MAP, PVRI and SVRI significantly decreased. DO2 and VO2 increased by 35% and 18% at 39℃ , 55% and 23% at 40℃ , 70% and 28% at 41℃ and by 88% and 31% at41.8℃.During WBH O2ER, PvO2 P(a-v)CO2 and pH (a-v) were maintained within normal range. At 41. 8℃ (2h) pH was lower than the normal range, at the end of WBH, hemodynamic and O2 metabolism parameters gradually returned to baseline levels. Conclusion The balance between oxygen delivery and oxygen consumption can be well maintained during WBH therapy under general anesthesia.