Gastric cancer (GC) continues to be 1 of the malignant tumors with high morbidity and mortality worldwide. Although the improvements in targeted inhibitor therapy have promoted survival, the first choice for GC patients is still surgery. However, prolonged surgery may tire surgeons and affect surgical outcomes.To detect whether different time-of-day radical gastrectomy influenced short-term and long-term surgical outcomes.This study included 117 patients between 2008 and 2012 who underwent a radical gastrectomy. These patients were grouped into the morning (before 13:00) and afternoon (after 13:00) groups or divided into 2 groups according to the median operation start time (before or after 11:23). Then, the relevant influence of the surgical start time was analyzed.The morning group (before 13:00) and the front median group (before 11:23) showed longer operative time (P = .008 and P = .016, respectively), lower estimated blood loss (P < .001 and P = .158, respectively), and longer time before resuming oral intake (P < .001 and P < .173, respectively) than the afternoon group (after 13:00) or latter median group (after 11:23). Starting the operation in the morning had no effect on the rate of postoperative complications. The operation start time had no significant influence on the overall survival of patients who underwent a radical gastrectomy. However, in subgroup analysis, patients who underwent a distal gastrectomy faced poor prognosis when their surgery started after 13:00 (P = .030).The results suggest that the operation start time might be an indicator of total operative time, estimated blood loss, and the time to resuming oral intake. The operation start time may also influence the prognosis of radical gastrectomy in patients with GC.