Objective To explore the clinicopathological characteristics of pancreatic neuroendocrine neoplasms ( P-NENs) and the prognosis .Methods The clinicopathological data of 72 patients with P-NENs in Sun Yat-Sen Memorial Hospital from December 2011 to September 2017 were analyzed retrospectively , and the gender, age, tumor size, local infiltration, neural invasion and distant metastasis were collected .According to the diagnostic criteria of P-NENs ( Chinese edition 2013 ) , tumor classification was determined by histological mitotic figure count and cell proliferation index ( Ki67 ) proliferation activity .Expressions of Syn , CgA, NSE and CD56 were determined by immunohistochemical staining .Results Seventy-two patients with P-NENs were enrolled, including 33.3％male(n=24) and 66.6％ female (n=48), and the median age was 56 years old (range:12-76).24 patients (33.3％) were NET G1,44 patients (61.1％) were NET G2 and 4 patients (5.6％) were NET G3.The mean size of tumor was 38.2 ±19.2 cm3 ( range:0.1-371 cm3 ). Immunohistochemistry staining positive rates for Syn , CgA, NSE and CD56 were 98.6％, 95.8％, 88.9％and 90.3％ respectively.Tumor classification was correlated with tumor size , local infiltration, perineural infiltration and distant (liver) metastasis (all P<0.05).There was no statistically significant differences on positive rate of Syn, CgA, NSE and CD56 among G1, G2 and G3.Conclusions Tumor classification, size, local invasion , perineural infiltration and distant ( liver ) metastasis were all important clinicopathological features and prognostic factors of P-NENs.Syn, CgA and Ki67 were essential immunohistochemical markers to diagnose P-NENs.