Substrate probe capable of detecting enzyme activity with high accuracy and a method for detecting the enzyme activity by a multi nuclear magnetic resonance method using the substrate probe. Multi-dimensional nuclear magnetic resonance is performed by using a substrate probe, which is used for measuring enzyme activity by a multi-dimensional nuclear magnetic resonance method and characterized by containing a enzyme recognition site that is selectively recognized by an active-state enzyme, as at least one constitutional unit, and a group to which at least three nuclear magnetic resonance active nuclei each having a nuclear spin and a different resonance frequency are connected, being present specifically to the enzyme recognition, thereby detecting presence of the substrate probe and the enzyme activity. Alternatively, imaging of the enzyme activity is performed by a multi-dimensional nuclear resonance imaging method.