Objective To evaluate the effects of low-dose epinephrine on cerebral oxygen saturation (rScO2) and awakening time during one-lung ventilation (OLV) for thoracic surgery. Methods Thirty consecutive patients undergoing lobectomy from March to July 2016 in our hospital were randomly divided into an epinephrine group (n=15, 8 males and 7 females at an average age of 58.70±11.40 years) or a saline group (n=15, 7 males and 8 females at an average age of 57.00±11.40 years). They were continuously infused with 0.01 μg/(kg·min) epinephrine or saline after general induction. Hemodynamics was maintained ±20% of the baseline value. All patients were ventilated by a pressure control mode during OLV with tidal volume of 5-8 ml/kg and end-tidal carbon dioxide tension (EtCO2) of 35-45 mm Hg. Regional cerebral oxygen saturation (rScO2) was monitored using near-infrared spectroscopy (NIRS) continuously. Results Compared with the saline group, the epinephrine group had a high rScO2 during OLV, with a statisitical significance at OLV 40 min and 50 min (67.76%±4.64% vs. 64.08%±3.07%, P=0.016; 67.25%±4.34% vs. 64.20%±3.37%, P=0.040). In addition, the awakening time of patients in the epinephrine group was shorter than that of the saline group (P=0.004), and the awakening time was associated with the duration of low-dose rScO2 (r=0.374). Conclusion Continuous infusion of 0.01 μg/(kg·min) could improve the rScO2 during OLV and shorten awakening time in thoracic surgery.