Gastroesophageal junction (GEJ) carcinoma is a rare but highly aggressive cancer. Adenocarcinomas of the GEJ (GEJAD) represent around 90% of all the GEJ cancers. In recent years, a significant increase in the prevalence of GEJAD has been recorded in many countries. In the current study, it was aimed to investigate the GEJAD in Iran and effect of multimodality therapy on survival rate. 246 patients with GEJAD have been investigated in terms of age, gender, Siewert types, tumor stage and history of cancer. To assess the impact of different types of treatments on survival outcomes, 124 patients that completed their treatment remained in the study. Analyses were performed using SPSS statistical software. Survival rates were estimated by use of the Kaplan-Meier method. All statistical tests were 2-sided, and p ≤ 0.05 indicated statistical significance. 198 males (80.5%) and 48 females (19.5 %) with mean ages of 67.52 and 64.23 years were studied respectively. The number of patients with Siewert type I (n= 107) was more than types II and III (n= 94 and 45 respectively). There was a significant correlation between Siewert types and tumor stage (p= 0.032). 15.1 % of patients had the family history of cancer in which 56.7% of them were related to the male first-degree relatives (father, brother). Overall mean and median survival time were 33.5 and 30 months respectively. There were significant differences between survival times based on different kinds of treatments (p=0.041). SUR→RT and CHT→SUR→RT, with two years' survival rates of 60% and 100% respectively; in addition, there were the most effective treatments for GEJAD patients. In order to obtain more significant results about the impact of SUR→RT and CHT→SUR→RT on survival time, more patients with long-term assessments need to be studied.