The star-shaped polymer is a type of branched polymer with special architecture containing at least three linear polymeric chains of com-parable lengths which radiate from one single multifunctional branched core [18–23]. This structure endows star-shaped polymer with specific space configuration including small radius of gyration and hydro-dynamic volume, which in turn affects the physiochemical properties of micellization in aqueous solution [19]. Compared with the linear ana-logues of identical molar masses, star-shaped polymer has advantages, such as better solubility, low viscosity and facile functionality of the terminal groups [22,24]. Therefore, introducing special topological structure into polyurethane architecture may provide a green approach to realize the easier dispersion of hydrophilic polyurethane into water phase without aiding of toxic solvent. Moreover, the increased cross-linking rate of the star shaped polyurethane may lead to compact structure of cured coatings, resulting in enhanced toughness, which can broaden WPU application on specific areas, such as marine antifouling [23]. There were some researches of star shaped PU, However, they were either solvent-based or used specific monomers which need extra synthesis under harsh conditions [20,19–23,25]. Wang et al [21] used pentaerythritol as the core to synthesize star-shaped polyurethane. It is found that star-shape polyurethane can self-assemble to form micelles in water, which benefits improving high solid content of WPU. How-ever, in their study, aggregations also occurred during dispersion pro-cess even under pre-dissolving in tetrahydrofuran. This is due to low hydrophilicity of polyurethane with ionic hydrophilic groups. Ad-ditionally, only drug delivery properties of stared-polyurethane mi-celles were investigated in their research. Hence, more performances and applications of star-shaped WPU remains to be studied.In this study, a four arms star-shaped polyurethane prepolymer based on pentaerythritol as core was synthesized via “arm first” ap-proach. Polytetrahydrofuran ether diol (PTMG) was choose as soft segment while isophorone diisocyanate (IPDI) were selected as hard segment. Dimethylol propionic acid (DMPA) and ethoxylated polymer diol (N-120) were incorporated as composite hydrophilic groups for enhanced hydrophilic efficiency of polyurethane molecular. As ex-pected, 45% solid content of waterborne polyurethane (WPU) disper-sions were obtained without aiding of organic solvent. Such new system realizes a facile solvent-free preparation of high solid contentwaterborne polyurethane with high performance. Particles size dis-tribution, viscosity and stability of the WPU dispersions were analyzed. The surface topography, phase structure, thermal and mechanical properties of the derived coatings were also studied. Moreover, high sold content WPU dispersions was applied on surface of leather for finishing for the first time. The performances of finished leather were evaluated to verify the applicability of WPU dispersions in leather in-dustry. The main objective of the work was to explore a green facile method to prepare high solid content WPU, as well to reveal the rela-tions between structure and properties for its potential applications.