This study aimed to identify the risk factors for postoperative complications after laparoscopic low anterior resection for the treatment of advanced rectal cancers. A prospectively maintained database was retrospectively analyzed. Oncological parameters in resected specimens and clinical risk factors for postoperative complications, including anastomotic leakage, were examined in patients with clinical stage II and III upper rectal cancer who underwent laparoscopic low anterior resection, including total mesorectal excision. Pathologic resection margins were negative in all patients. Postoperative complications occurred in 22 patients (25.9%), which is similar to incidence rates in previous studies. In multivariate analysis, tumor size (≥4 cm) and tumor category (T4) were independent risk factors for postoperative complications. Precise pretreatment diagnoses with locoregional evaluations are essential for the selection of appropriate patients for laparoscopic rectal resection. Despite quality results from laparoscopic low anterior resection for the treatment of advanced rectal cancer, we must attempt to reduce postoperative complications.