［Objective］To obtain hydroxyacrylic dispersions with both low viscosity and excellent alkali resistance.［Methods］Using butyl acrylate（BA）as the soft monomer，styrene（St）and methyl methacrylate（MMA） as hard monomers，we focused on adjusting the proportion of four hydroxyl-containing monomers［hydroxyethyl methacrylate（HEMA）， hydroxypropyl methacrylate（HPMA）， hydroxyethyl acrylate（HEA） and hydroxypropyl acrylate（HPA）］ to prepare hydroxyacrylicdispersions. The effects of type and content of four hydroxyl monomer combinations on the particle size， viscosity and appearance of dispersion were investigated. Additionally，their impacts on properties of waterborne two-component polyurethane coatings，such as gloss，hardness，ethanol wipe resistance，and alkali resistance were evaluated.［Results］When the hydroxyl monomer combination was HEA/HPA with HPA accounting for 25% of the hydroxyl monomers in core，the viscosity of the prepared hydroxyacrylic dispersion was reduced to 464. 4 mPa·s. Furthermore，the prepared coating does not bubble or change color after being soaked in 5%NaOH solution for 8 days，its ethanol wipe resistance exceeded 220 cycles. The 20°/60° gloss values reached 82. 4/92. 5，with a hardness of 2H.［Conclusion］ The "hydrophilic-core hydrophobic-shell" structure composed of composite hydroxylmonomers can effectively reduce the viscosity and particle size of dispersion，which exhibits goodstability with a milky white appearance and a blue light. HEA has high reactivity with isocyanategroups，leading to a densely crosslinked paint film with better alkali resistance and solvent wiperesistance. A mass ratio of HEA to HPA of 3∶1 in the core component maximizes the retention of theseadvantages while significantly reducing the application viscosity，thus overcoming the drawbacks caused by the use of a single hydroxyl monomer.