The invention relates to a micro-array 
biochip, and a preparation method and an application of the micro-array 
biochip. The micro-array 
biochip comprises a 
glass chip substrate and a modification layer. The modification layer comprises a 
chromium layer, a silver and / or 
gold layer, a self-
assembly monomolecular layer, and a photo-cross-linking agent and high-molecular layer, which are overlaid in sequential on the surface of the 
glass chip substrate. The invention also provides a 
protein micro-array, a method for preparing the 
protein micro-array, and an application of the 
protein micro-array to detect micromolecule 
medicine. According to the invention, three-dimensional high-molecular 
surface modification of the micro-array biochip is completed by the method, and the fixation amount of protein on the surface of the micro-array biochip can be effectively improved, so that micromolecule, hard to detect in the prior art, can be detected without marking, in accuracy, and in 
high flux. The micro-array biochip is of great significance to the field, such as 
molecular biology study and medicinal development.