Objective: To explore the effect of islet neogenesis-associated protein(INGAP) on islet function, apoptosis, gene expression and insulin secretion in vitro. Methods:Islets isolated from male adult Wistar rats were cultured in RPMI 1640 with or without INGAP(10 μg/ml). After 24 h, cultured islets were collected, the degree of apoptosis, glucose-stimulated insulin secretion were measured and the expression of genes Bcl-2 and Akt were detected by RT-PCR assay. Results: ① Glucose stimulated insulin secretion(GSIS) stimulated by 16.7 mmol/L glucose was increased in islets co-cultured with INGAP of compared with islets cultured without INGAP [(185.00±20.01) μU/ml vs.(58.67±17.03) μU/ml]; the stimulating index of islets of INGAP group(5.10±2.35) was higher than that of control (no INGAP group:1.92±0.42). ②Gene expression of Bcl-2 and Akt in INGAP group were increased compared with those of control group(0.607±0.217 vs. 0.503±0.209;1.115±0.189 vs. 0.935±0.162).③Islets survival in co-cultured pancreatic islet group(2 685.45±5.08)was higher than that of control group(2 108.65±4.02). Conclusion:INGAP can reduce the apoptosis of pancreatic islets and maintain islet function after co-culture in vitro.