The invention discloses an automobile water-based dual-component middle 
coating excellent in performance and a preparation method thereof. The water-based middle 
coating is composed of a component A and a component B. The component A is composed of hydroxy 
acrylic resin, 
powder syrup, auxiliaries and cosolvent, wherein 
powder syrup contains deionized water, amine neutralizer, auxiliaries, 
extender pigment and 
pigment. The component B is composed of a curing agent, auxiliaries and cosolvent. After being put in according to the formula of the 
powder syrup of the component A, materials are dispersed at a high speed for 15 min and then enter a 
grinding machine to be ground till the 
granularity is smaller than 30 micron, then powder syrup is obtained, and hydroxy 
acrylic resin, powder syrup, auxiliaries and cosolvent are evenly mixed to obtain the component A. The component A and the component B are mixed in certain proportion, 
viscosity is adjusted by adding deionized water, and a middle 
coating film is obtained through spraying construction. By means of the water-based middle coating, the water-based performance of the automobile middle coating is achieved, the VOC content is greatly decreased, and excellent comprehensive performance is achieved.