A substantial amount of a marker reagent associated with a measurement is measured in a marker reagent measurement area, and the substantial amount of the marker reagent is reflected by a result obtained in a reaction result measurement area where a reaction with a measurement target in an inspection target solution is measured. Thereby, an influence of external environmental factors, factors in a property of the inspection target solution, an erroneous operation in a measurement operation or the like is eliminated, whereby a chromatography measuring method employing a biosensor with higher accuracy and higher reliability can be provided.