〔Abstract〕 Objective To investigate the expression of KIAA1199 in pancreatic ductal adenocarcinoma(PDAC) and its clinical significance. Methods 60 PDAC tissues confirmed by pathological diagnosis and 20 pancreatic tissues adjacent to the cancer were collected, and immunohistochemical staining experiments were performed to detect the expression of KIAA1199 gene in paraffin sections. And we analyzed its relationship with related clinicopathological factors and tumor survival time after surgery. At the same time, Western blot and qRT-PCR experiments were used to detect the expression of KIAA1199 in 10 pairs of fresh frozen pancreatic cancer specimens and corresponding adjacent tissues. Results The high expression rates of KIAA1199 in PDAC tissue and adjacent tissues were 70.0%(42/60) and 25.0%(5/20), and the differences were statistically significant(P<0.05). Statistical analysis showed that clinical factors such as lymph node metastasis(P<0.05), differentiation degree(P=0.010), nerve invasion(P=0.016), TNM stage(P=0.047) were closely related to the expression of KIAA1199(P<0.05).However, factors such as age(P=0.206), gender(P=0.515), and tumor location(P=0.726) were not significantly related to the expression of KIAA1199(P>0.05).Using Kaplan-Meier method for survival analysis, the median survival time of KIAA1199 positive overall survival(OS) was 13.5 months and the median survival time of negatively expressed OS was 17 months. The median survival time for disease-free survival(DFS) in KIAA1199-positive patients was 10 months, while the median survival time for DFS in negative-expression patients was 13.5 months. The difference was statistically significant(P<0.05).Western blot and qRT-PCR experiments confirmed that the expression of KIAA1199 in PDAC tissues was higher than that in adjacent tissues, and the difference was statistically significant(P=0.0001,P<0.0001). Conclusion KIAA1199 gene is highly expressed in PDAC tissues, which is closely related to the pathological differentiation of PDAC, TNM stage, nerve infiltration, lymph node metastasis and the prognosis survival time of patients. KIAA1199 may be a new biomarker for predicting PDAC in the future.