The invention provides hydroxyl 
acrylic resin and a preparation method thereof. The hydroxyl 
acrylic resin is prepared by performing a reaction on the following raw materials in parts by weight: 60 to 90 parts of hard monomers, 10 to 30 parts of soft monomers, 5 to 20 parts of hydroxyl monomers, 0.5 to 5 parts of carboxyl monomers, 1 to 5 parts of initiators, and 1 to 5 parts of 
chain transfer agents. The dosages of the hard monomers are more, so that the 
hardness of the prepared hydroxyl 
acrylic resin is strengthened; the dosages of the soft monomers are proper, so that the proper 
toughness of the hydroxyl acrylic resin can be maintained. Compared with the prior art, the dosages of the hydroxyl monomers are reduced to some extent, so that the surface 
drying speed of the hydroxyl acrylic resin is further increased, and the hydroxyl acrylic resin has a higher glass-
transition temperature. At the same time, the content of the hydroxyl is moderate, so that the hydroxyl acrylic resin can maintain excellent crosslink density and 
solvent resistance; moreover, the 
chain transfer agents are utilized to control the molecular weight of the hydroxyl acrylic resin, so that the hydroxyl acrylic resin is not only relatively higher in 
solid contents, but also lower in 
viscosity.