The aim of the present study was to analyze and summarize the clinicopathological characteristics and factors affecting prognosis for patients with gastrointestinal neuroendocrine neoplasms (GINENs). Retrospective analysis was conducted on the clinicopathological data of 74 patients who were diagnosed with GINEN, and immunohistochemical methods were used to detect the expression levels of relevant markers [synaptophysin (Syn), chromogranin A (CgA) and Ki-67]. Among the 74 cases with GINEN, there were 39 males and 35 females, with an average age of 56.9 years. There were 32 neoplasms in the rectum, 29 in the stomach, 6 in the colon, 2 in the small intestine and 5 in the appendix. All 74 cases underwent surgical resection. According to the World Health Organization Classification of Tumors of the Digestive System (2010), the diagnosis of the 74 cases showed 41 cases (55.4%) of neuroendocrine tumor (NET; 25 cases of G1 and 16 cases of G2), 21 cases (28.4%) of neuroendocrine carcinoma (NEC) and 12 cases (16.2%) of mixed adenoneuroendocrine carcinoma (MANEC). Additionally, 19 cases had metastasis to lymph nodes. During 10-34 months of follow-up, 15 patients had distant metastasis and 24 patients succumbed, and the accumulative survival rate in 1 or 2 years was 87.8 and 74.3%, respectively. Six factors, namely neoplasm size, depth of invasion, lymph node metastasis, distant metastasis, pathological type and the expression or lack of expression of CgA, significantly affected the survival time of patients. Definitive diagnosis of GINEN mainly relies on pathological diagnosis. GINENs with different histopathological types and grading have different clinicopathological characteristics and prognosis: NETs are mainly early lesions with a good prognosis, whereas NECs and MANECs have high malignancy and strong invasion with a worse prognosis.