The present invention relates to a method for preparing pearlescent pigment through metal oxide coating based on a sheet-like substrate, and the obtained pearlescent pigment. The present invention further relates to a method for preparing pearlescent pigment through coating a sheet-like substrate by hydrolyzing metal salt under an acid condition, wherein a pH value is adjusted by using inorganics such as MgO, MgOH or CaCO3 that does not dissolve in water but can dissolve through reacting with an acid. According to the method, no free metal oxide is generated when the metal salt is hydrolyzed, so that the production cost is reduced, product quality is improved, problems possibly generated in an application process of the product are avoided, and a production process is more environment-friendly.