目的:通过1例病例报道分析小肠腺癌的诊疗过程,从临床症状、影像特点及鉴别诊断分析并进行总结,增加对小肠腺癌的认识以及相关疾病的鉴别。方法:报道小肠腺癌误诊为肠系膜上动脉综合征1例。结果:前期因误诊为肠系膜上动脉综合征予以保守治疗,后因症状未明显改善行手术治疗,术后最终病理结果,诊断为小肠腺癌。现患者术后经过5个周期化疗,随诊至今患者暂无转移复发。结论:小肠腺癌是一种罕见的消化道恶性肿瘤,因其症状不典型,无特异的实验室检查及影像学检查,在临床上容易造成误诊,延误患者治疗。在诊疗过程中,应结合多种影像学检查及患者症状,做出正确的治疗方法,以免延误患者治疗。Objective: To analyze the diagnosis and treatment process of small bowel adenocarcinoma through a case report, analyze and summarize the clinical symptoms, imaging characteristics and differential diagnosis, and increase the understanding of small bowel adenocarcinoma and the identification of related diseases. Methods: One case of small bowel adenocarcinoma was misdiagnosed as superior mesenteric artery syndrome. Results: Conservative treatment was given for misdiagnosis of superior mesenteric artery syndrome in the early stage, and surgery was performed later due to no significant improvement in symptoms, and the final pathological result after surgery was diagnosed as adenocarcinoma of the small intestine. The current patient has undergone 5 cycles of chemotherapy after surgery, and there has been no metastasis recurrence so far. Conclusion: Adenocarcinoma of the small intestine is a rare malignant tumor of the digestive tract, which is easy to cause misdiagnosis and delay the treatment of patients due to its atypical symptoms and no specific laboratory tests and imaging examinations. In the process of diagnosis and treatment, the correct treatment should be made in combination with a variety of imaging examinations and the pati