Provided is a method for the real-time visualization of an endogenous biomolecule to clarify the mechanisms of various diseases and enable diagnosis and treatment of these diseases. Specifically provided is a novel method for visualizing an endogenous biomolecule by using a magnetic resonance method (including Overhauser MRI and the electron spin resonance method). The aforesaid visualization method, whereby an endogenous biomolecule is visualized on a real-time basis, comprises: a step for treating a living organism to be examined by a magnetic resonance method and thus acquiring data of the endogenous biomolecule; a step for processing the data of the endogenous biomolecule thus obtained to give imaging data; and a step for displaying the imaging data thus obtained.