The digestive tract tumor disease is a serious threat to human health. The effective identification of digestive tract tumor markers with specific characteristics is the key to the diagnosis, treatment, recognition, and rehabilitation analysis of digestive tract tumor diseases. Public medical data resource platforms represented by Oncomine, Gene Expression Profiling Interactive Analysis (GEPIA), and Human Protein Atlas (HPA) databases provide a new path for knowledge management and knowledge discovery in the medical field. Therefore, a computational analysis framework for tumor marker recognition was established to mine from massive and diversified data sets and explore the diagnosis, expression, and prognosis of Non-SMC Condensin I Complex, Subunit G (NCAPG) in gastrointestinal tumors. Patient survival and correlation analyses suggested the mRNA and protein levels of NCAPG were highly expressed in different digestive tract tumors. This study provides new treatment methods for patients with gastrointestinal cancer and a reference for the public.