The dewetting dynamics of polystyrene(PS) blend thin films of low energy fluorocarbon chain end functional PS-F 17.3K and PS-F 35.5K with normal PS 34.5K on the 100K poly(methyl methacrylate)(PMMA) surface have been investigated.Optical microscopy was used to follow the dewetting process.XPS and AFM have been used to detect the surface segregation of fluorocarbon chain end at the surface and the equilibrium contact angle of PS droplet on PMMA.The surface segregation of low energy fluorocarbon chain end increases and the equilibrium contact angle of PS droplet decreases with increasing of the end functional polystyrene bulk fraction and decreasing of molecular weight. The segregation of fluorocarbon chain end to the surface makes the surface tension and equilibrium contact angle decrease.The dewetting velocity of PS films on PMMAwas found to decrease as a function of the surface tension and equilibrium contact angle. It is in agreement with the theoretical prediction.