The work aims to construct the UV-shielding and transparent coating on poly(lactic acid) (PLA) film via hydrogen-bonded layer-by-layer assembly of hydroxypropyl methyl cellulose (HPMC) and tannic acid (TA). The morphologies of the surface and cross-section of the film were observed by the polarized optical microscopy (POM), the UV-shielding property was measured by the Ultraviolet-visible (UV-vis) spectrophotometer, and the mechanical property of the film was measured by the universal electronic testing machine. Compared with the original PLA film, with the increase of the number of assembly layers, the UV-shielding property was increased, the transparency was almost unchanged, and the mechanical properties decreased slightly. Some experimental and theoretical basis is provided for the design and preparation of UV-shielding and transparent coating on the packaging film.