Objective:To investigate cytologic features,immunocytochemical profiles and differential diagnoses of solid-pseudopapillary neoplasms (SPN) of the pancreas in endoscopic ultrasound-guided fine needle aspiration (EUS-FNA)specimen. Methods:The cytopathological and immunocytochemical features were studied in 7 cases of SPN,who were diagnosed by EUS-FNA cytology and were confirmed by histopathology. Results:Samples of EUS-FNA gotten from SPN were usually highly cellular. Tumor cells were usually small and uniform,round-to-plasmacytoid,had pale-to-granular cytoplasm with vacuoles. The nuclei of neoplastic cells were usually round or orbicular-ovate,with smooth contours,fine and evenly dispersed granular chromatin. Nucleoli were not seen or inconspicuous. The neoplastic cells were presented as diffused distribution,rosette/acinar pattern,and more specifically,papillae with fibrovascular cores. Immunocytochemical staining was performed on 5 cases. Vimentin,progesterone receptor,β-catenin,CD10,CD56 and α-1-antitrypsin showed strong positivity in all 5 cases,and synaptophysin,chromogranin A,cytokeratin AE1/AE3 as well as CD99 variable positivity in some of the cases. Conclusion:Cyto-morphological characteristics of SPN includes small uniform tumor cells,which are disperse or arranged in papillae with fibrovascular cores. Differential diagnoses of SPN include pancreatic endocrine neoplasm and acinar cell carcinoma etc. The expression of β-catenin,CD10,CD56,vimentin,progesterone receptor and CD99 can promote the diagnosis of SPN.