Diamond-like carbon (DLC) films have been deposited on Si(100) by pulsed laser deposition (PLD) using 355 nm (Nd:YAG) laser. In order to investigate the factor that dominates the electron field emission behavior of DLC film, structural and electrical properties have been studied as a function of anneal temperature. Degradation of DLC film properties began to be observed above 400 degrees C but, in case of plasmon energy loss and emission behavior, there were variations of properties at 300 degrees C. From these results, we are convinced that anneal treatment modifies sp(3)/sp(2) bonding ratio in surface as well as bulk of film but the anneal effect is more intensified on the surface than the bulk of DLC film. It is also observed that the electron field emission property is affected by the modification of sp(3)/sp(2) bonding ratio in the film surface.