Molecular dynamics simulations are performed to study the growth of diamond-like carbon (DLC) films with a thickness of 2—3nm on diamond (100) substrate. Some important structural properties characterizing the quality of the deposited films, such as sp3 hybridization fraction, film density, radial distribution function, are analyzed which turn out to be consistent with experimental results. The incident energy has significant influence on the structural properties, and hence film properties. Optimal properties are obtained when kinetic energy of the incident atoms is in the range 20—60eV. The incidence of energetic species is prerequisite for growing homogeneous, continuous and compact films. A steady-state intrinsic region is required to guarantee outstanding mechanical properties of the thin film.