ObjectiveTo compare the clinical efficacy of different surgical approaches for Siewert type Ⅱ adenocarcinoma of esophagogastric junction (AEG). MethodsThe clinical data of the patients with Siewert type Ⅱ AEG who received sugeries in the Department of Thoracic Surgery of Gansu Provincial People's Hospital from August 2014 to December 2019 were retrospectively analyzed. The patients were divided into two groups according to the surgical approach: a transabdominal group (transabdominal diaphragmatic esophageal hiatus approach) and a combined group (thoracoabdominal combined with right thoracic approach). Perioperative clinical data and postoperative follow-up data were collected to compare the short- and long-term efficacy of the two groups. Results A total of 87 patients were enrolled. There were 48 patients (31 males and 17 females, with an average age of 60.85±8.47 years) in the transabdominal group, and 39 patients (25 males and 14 females, with an average age of 61.13±8.51 years) in the combined group. There was no statistical difference between the two groups in the baseline indicators such as gender, age, tumor size and stage (P>0.05). Compared with the combined group, the operation time, intraoperative blood loss, postoperative bed rest time, postoperative total drainage volume were shorter or less, and the visual analogue scale score on the 3rd day after surgery were lower in the transabdominal group (P<0.05). However, the total number of lymph nodes dissected, the number of thoracic lymph nodes dissected and the number of positive thoracic lymph nodes in the combined group were larger than those in the transabdominal group, and the differences were statistically significant (P=0.001). The median survival time in the combined group and transabdominal group was 25.85 months and 20.86 months, respectively. The 3-year overall survival rate of the combined group was higher than that of the transabdominal group (46.2% vs. 38.9%, χ2=5.995, P=0.014). However, there was no statistical difference between the two groups in the postoperative catheter time, esophageal and gastric resection margin distance, number of abdominal lymph nodes dissected, number of positive abdominal lymph nodes, or incidence of postoperative complications (P>0.05). ConclusionFor patients with Siewert type Ⅱ adenocarcinoma of esophagogastric junction, thoracoabdominal combined with right thoracic approach is safe and effective, and has advantages in thoracic lymph node dissection, bringing more benefits to the patients, so it is recommended to be popularized in clinical practice.