Conductive LaNiO3 (LNO) thin films were prepared on Si(000 by pulsed laser deposition and their microstructures were investigated using synchrotron X-ray scattering and atomic force microscopy. We observed that the surface morphology of the LNO thin films was extremely smooth with typically a 1.0-nm root-mean-squared roughness for films up to 360 nm in thickness and the film strain increased monotonically with the film thickness, suggesting that the LNO/Si(001) films be grown with a layer-like growth mode. Grown with the (001) preferred orientation, the LNO films showed a significant anisotropic structural order; the coherence length of the out-of-plane stacking order was one order of magnitude larger than that of the in-plane atomic order.