Granular packing of microsized particles with different size distributions and contact force models is studied using discrete element method (DEM). Three kinds of size distributions, monosized, uniform, and Gaussian, with mean diameter of 50, 60, and 70 μm are studied. Two aspects of microscale particle packing issues are addressed: one is the importance of van der Waals force when the particle size approaching to microscale, the other one is the structure variation caused by different contact force models. The results indicate that compared with contact force, the van der Waals force contributes very insignificantly to the final packing structure. The packing structures obtained using two different force models are similar to each other. The effects of particle size and its distribution on the packing structure are more significant than the force model.