Abstract: Phycocyanin(C-PC)is a natural water-soluble and nontoxic functional protein extracted from Spirulina platensis. In this study,the effects of C-PC on proliferation,apoptosis and migration in non-small cell lung cancer H1299 cells by using MTT assay,cloning formation assay,flow cytometry and wound-healing assay. The results showed that phycocyanin could significantly(p<0.05)decrease the cell survival rate. C-PC could induce S phase arrest by regulating the expression levels of cell cycle related proteins cyclinA,CDK2,and P21.Furthermore,C-PC induced apoptosis of H1299 cells by regulating apoptotic genes including bad,bax,bcl-xL,and bcl-2.The results of wound-healing assay showed that C-PC inhibited cell migration through regulating MMP-9(matrix metalloproteinase-9)and MMP-2(matrix metalloproteinase-2). These results indicated that C-PC could induce cell cycle S phase arrest,regulate the expression of cell cycle,migration and apoptosis genes,resulting in the growth inhibition and apoptosis of H1299 cells,which would provide a theoretical basis for the development of novel natural functional substances and lung cancer treatment.