Almost one million new cases of gastric cancer were estimated to have occurred in 2012, making it the fifth most common malignancy in the world. It is also the third leading cause of cancer death of people of both genders worldwide. The aim of this study is to evaluate the significance of some prognostic factors for gastric cancer survival in 155 patients treated at Aleksandrovska University Hospital, Sofia, Bulgaria. This retrospective study includes patients diagnosed and treated at Department of Surgery of Aleksandrovska University Hospital for the 9-years period of time between January 2005 and December 2013. We classified the prognostic factors as patient-related (age at diagnosis specification, gender, and blood type), tumor-related (N-stage, tumor differentiation, process localization), and treatment related (patients who had radical surgery and adjuvant therapy). We found that blood type is the only statistically significant prognostic factor for overall survival from the patients-related group of factors (p = 0.030). The only prognostic factor from the ones in the tumor related group remains the N-stage according to the TNM classification (p = 0.003). Adjuvant could not prove its value for overall survival (p = 0.675).