Postresuscitation care bundle treatment after return of spontaneous circulation in patients experiencing in-hospital cardiac arrest can improve patients' survival and quality of life. The aim of the study was to evaluate the efficacy and safety of combined therapy of Shenfu injection and postresuscitation care bundle in these patients. Prospective, randomized, controlled clinical study. Fifty hospitals in China. Adult patients had experienced in-hospital cardiac arrest between 2012 and 2015. Based on the standardized postresuscitation care bundle treatment, patients were randomized to a Shenfu injection group (Shenfu injection + postresuscitation care bundle) or control group (postresuscitation care bundle) for 14 days or until hospital discharge. In the Shenfu injection group, 100 mL Shenfu injection was additionally administered via continuous IV infusion, bid. The primary outcome was 28-day survival after randomization. The secondary outcomes included 90-day survival as well as the duration of mechanical ventilation and the hospital stay and the total cost of hospitalization. Of 1,022 patients enrolled, a total of 978 patients were allocated to the two groups: the control (n = 486) and Shenfu injection (n = 492) groups. The Shenfu injection group had a significantly greater 28-day survival rate (42.7%) than the control group (30.1%). Also, the Shenfu injection group had a significantly higher survival rate at 90 days (39.6%) than the control group (25.9%). Compared with patients in the control group, patients in the Shenfu injection group had lower risks of 28-day mortality (hazard ratio, 0.61; 95% CI, 0.43-0.89; p = 0.009) and 90-day mortality (hazard ratio, 0.55; 95% CI, 0.38-0.79; p = 0.002). In the Shenfu injection group, the duration of mechanical ventilation (8.6 ± 3.2 vs 12.7 ± 7.9 d; p < 0.001) and the hospital stay (8.7 ± 5.9 vs 13.2 ± 8.1 d; p < 0.001) were significantly less than in the control group. Irreversible brain damage was the main cause of death in both groups. No serious drug-related adverse event was recorded. This study demonstrates that Shenfu injection in combination with conventional postresuscitation care bundle treatment is effective at improving clinical outcomes in patients with return of spontaneous circulation after in-hospital cardiac arrest.