The study presented a rare case of jejunal adenocarcinoma in a 60-year-old patient with symptoms of high subileus. No risk factors or coexisting diseases, which predispose towards intestinal cancer were detected. The study contained a description of the performed surgical procedure. The presented case illustrated the diagnostic and therapeutic difficulties in patients with small intestinal cancer. The low prevalence of small intestinal cancer makes no clear standards of mid- and postoperative treatment, including the qualification for adjuvant chemotherapy. The aim of this study was to broaden the knowledge concerning the presented symptoms and diagnostic test abnormalities, which, in case of rare diseases, is based on single patient reports. Furthermore, according to reference analyses, postoperative recommendations were presented, including diagnostics towards coexisting predisposing diseases.