To investigate the mechanism of phycocyanin (PC) on improving insulin resistance (IR) in vitro, high concentration of insulin was used to induce IR model. HepG2 cells were treated with five insulin concentration gradients (10-9, 10-8 , 10-7, 10-6, 10-5μmol/L) and six time gradients (0,12, 24,36, 48,72h), respectively. According to the results of glucose consumption and cell viability, the optimal concentration and time of insulin resistance model of HepG2 (IR-HepG2) cells were determined. After PC intervention, glucose consumption, glycogen synthesis and cell viability of normal and IR-HepG2 cells were detected, respectively. RT-qPCR and Western blot were used to investigate the possible mechanism. The results showed that IR-HepG2 cells was optimally established with 10-7μmol/L insulin treatment for 36h. Different concentrations of PC could promote glucose consumption of IR-HepG2 cells. PC could up-regulate the transcription levels of IRS1, IRS2, GLUT1 and GLUT4 genes in both normal and IR-HepG2 cells, and increased the phosphorylated protein expression levels of IRS1, AMPK, GSK-3β and AKT. PC might significantly promote glucose consumption in IR-HepG2 cells by activating IRS1/AKT signaling pathway and increasing the phosphorylation of AMPK, also activating expression of GLUT1 and GLUT4 genes ecoding glucose transporter,and accelerate glucose utilization and improve insulin resistance in IR-HepG2 cell. This study indicated that PC had a potential role in preventing or improving hepatic insulin resistance of type 2 diabetes mellitus.