Objective To observe the effects of resveratrol-loaded arginine glycine aspartic acid（RGD）peptide modified PEG-PEI nanoparticles on proliferation and cell cycle of colorectal cancer cell line SW620. Methods Resveratrol-loaded RGD peptide modified PEG-PEI nanoparticles were constructed. The diameter，encapsulation efficiency and the release rate of the nanocomposite in vitro and its effects on proliferation, cell cycle and apoptosis of human colorectal cancer cell line SW620 were measured. Results Resveratrol-loaded RGD peptide modified PEG-PEI nanoparticles were constructed successfully. The average diameter of nanoparticles was（124.9±36.0）nm，the average encapsulation efficiency was（85.3±5.6）％，and（72.5±8.3）％ of the resveratrol was released in 3 days. The SW620 proliferation could be significantly inhibited by resveratrol-loaded nanoparticles compared with free resveratrol at the concentrations of 60， 80， and 100μmol／L（P＜0.05）. SW620 in S phase increased significantly by resveratrol-loaded nanoparticles at the concentrations of 40 and 80μmol／L，while the proportion of apoptotic cells increased significantly at the concentration of 40μmol／L. Conclusion The resveratrolloaded nanoparticles are able to induce apoptosis，have antiproliferative activity on human colorectal cancer cell line SW620 and increase the ratio of phase S cells，which makes a good prospect.