Poly (vinyl alcohol) (PVA), a multi-hydroxyl polymer with high polarity, shows excellent comprehensive properties and has been developed very fast in recent years. However, the narrow thermal processing window between the melting and decomposition temperature results in the difficulty in thermal processing of PVA, which seriously hinders the further preparation of PVA-based micro/nanocomposites with high performance. In this paper, the novel highly filled PVA based composites with high performances were prepared by combing the molecular complexation and the solid state shear milling (S3M) technologies developed in our research group, and their micro-injection molding and 3D printing were studied. Through molecular complexation formed among amido contained compounds, water and PVA, wide thermal processing window (≥ 80oC) of PVA was obtained, and PVA based biomedical micro/nanocomposites, e.g., PVA/hydroxyapatite (HA), PVA/gelatine/HA and PVA/β-tricalcium phosphate(β-TCP), etc., were prepared in a quite large scale via thermal processing by taking advantages of the pretty good compatibility of PVA and organic or inorganic fillers. Adopting S3M technology, the excellent dispersion of bio-micro/nanoparticles, even at high content (40wt%), in PVA matrix was achieved. Accordingly, the micro-injection molding and Fused Deposition Modeling (FDM) of PVA based composites were successfully realized, and the micro-injection samples with higher crystallinity and higher mechanical properties than these obtained by conventional injection molding, and 3D printing parts with complicated shapes as well as good cell compatibility and blood compatibility, were obtained. These functional PVA based Micro/nanocomposites have potential applications in drug delivery, articular cartilage, biological scaffold, etc. This work was supported by the National Natural Science Foundation of China (51433006, 51010004).