The present invention provides a measuring method for at least one of a kinase forward reaction substrate, a phosphorylated product thereof, and a precursor thereof, and includes a step of conducting an enzymatic cycling reaction by bringing at least a kinase, a first nucleotide coenzyme of the kinase, and a second nucleotide coenzyme having a different nucleoside moiety from the first nucleotide coenzyme into contact with a sample; a step of detecting a signal corresponding to a change of at least one of the first nucleotide coenzyme and a conversion product thereof, and the second nucleotide coenzyme and a conversion product thereof; and (3) a step of calculating, on the basis of the detected change of the signal, an amount of the kinase forward reaction substrate and/or the phosphorylated product thereof contained in the sample.