This paper deals with molecular dynamics simulation of the wrinkling deformation of a zigzag square sin-gle-layer graphene sheet (SLGS) subjected to gradient tensions． In the investigation，the formation and evolution of the wrinkles on graphene surface are analyzed，and the effects of boundary and loading conditions on the wrink-ling deformation are explored． Then，the variations of the wrinkling amplitude，the wavelength，the out-of-plane displacement and the direction angle with the loading displacement are revealed，and the effects of graphene size，temperature and loading grad on the wrinkling are discussed． It is found that (1) the formation and evolution process of wrinkles can be divided into four stages，namely the prophase stage，the metaphase stage，the ana-phase stage and the telophase stage; (2) with the increase in loading displacement，the wrinkling amplitude，the ratio of amplitude to wavelength and the maximum out-of-plane displacement all increase，while the wrinkling wavelength and the direction angle decrease; and (3) both the size and the temperature remarkably affect the gra-phene wrinkling，while the loading grad has little effect on the wrinkling．