Provided is a composition for detecting a protein, containing a tyrosine oxide-coupled biomaterial. Various diseases may be easily and rapidly diagnosed by easily detecting the composition containing a tyrosine oxide-coupled biomaterial according to the present invention, by identifying a color of the protein bound with a tyrosine oxide-coupled biomaterial prepared by binding tyrosine oxide, which is a natural pigment present in a living body, with the biomaterial. Accordingly, the composition of the present invention may be used to easily and rapidly diagnose various diseases in real time in an operating room, and may usefully replace conventional histological analysis without a secondary antibody reaction and a final operation of color expression.