Curative resection for colorectal cancer and their synchronous liver metastases are increasingly performed. However, it is still unclear whether the operative order affects the surgical outcome in laparoscopic simultaneous resection of primary and liver metastatic lesions. A total of 27 patients underwent laparoscopic simultaneous resection of primary colorectal cancer and liver metastases at Kumamoto University Hospital. They were divided into two groups based on the order of resection: Colon-first (n=11) and liver-first (n=16) groups. The surgical outcomes between the two groups were retrospectively compared. There was no significant difference in the perioperative surgical outcomes between the two groups except for operative blood loss, which was significantly less in the liver-first group [164 (range=5-820) versus 560 (range=95-2,016) ml, respectively] (p=0.0299). In the simultaneous resection of primary and liver metastatic lesions, the operative order does not affect the short-term surgical outcomes except for operative blood loss.