The invention discloses water-based acrylic polyurethane amino baking pearlescent paint and a preparation method thereof. The water-based acrylic polyurethane amino baking pearlescent paint is prepared from the following components including hydroxyl acrylic dispersion, water-based amino resin, a pH regulator, a cosolvent, a closed isocyanate curing agent, pearl powder, a defoaming agent, a dispersing agent, a wetting agent, water, a pearl powder directional arrangement agent and a thickening agent, wherein the closed isocyanate curing agent contains aliphatic chain segments, isocyanurate rings and aromatic ring groups. The invention also discloses a preparation method of the water-based pearlescent paint. The water-based pearlescent paint disclosed by the invention has low VOC content, excellent environmental protection performance, high paint film crosslinking density, full paint film, high glossiness, high hardness, good mechanical property and excellent adhesive force. The water-based pearlescent paint has the advantages of good directional arrangement effect of the pearlescent powder and excellent pearlescent effect and is suitable for mechanical equipment. Meanwhile, due to the single component, the construction is convenient, the performance is stable, and the application prospect is wide.