The classical model for a thin film, based on continuum theory, is independent of size, and ignores surface effects. But the surface-to-bulk ratio becomes very large in small-scale structures such as nanofilms, nanowires, and nanobeams, and surface effects play an important role. Molecular dynamics simulation has been a conventional way to analyze these ultrathin structures, but structures in the range between submicro and micro are difficult to analyze by molecular dynamics simulation due to the restrictions of computing resources and time. In the present study, a continuum-based, size-dependent model is developed for predicting the thermomechanical properties of nanoscale structures, especially thin films. The proposed continuum-based thin plate finite element is efficient and reliable for the prediction of nanoscale film behavior.