The diagnosis support apparatus includes a reference region to be treated as a reference of the state of generation of fluorescence from fluorescence images obtained by capturing fluorescence generated when excitation light is irradiated to a desired subject in the subject, An area extracting unit that performs processing for extracting a target region to be handled as a state comparison target and a luminance value of each pixel included in the reference region and a luminance value of each pixel included in the region of interest , An arithmetic processing unit that performs arithmetic processing for calculating an arithmetic value indicating the intensity ratio of the fluorescence of the region of interest with respect to the reference region, a storage section that stores the arithmetic value calculated by the arithmetic processing section, And an image processing unit that performs processing for displaying on the display device information indicating a time-dependent change in the calculated value.診断支援装置は、被検体内の所望の被写体に励起光を照射した際に発生する蛍光を撮像して得た蛍光画像の中から、蛍光の発生状態の基準として扱う基準領域と、蛍光の発生状態の比較対象として扱う注目領域と、をそれぞれ抽出するための処理を行う領域抽出部と、基準領域に含まれる各画素の輝度値と、注目領域に含まれる各画素の輝度値と、に基づき、基準領域に対する注目領域の蛍光の強度比を示す演算値を算出するための演算処理を行う演算処理部と、演算処理部により算出された演算値を格納する記憶部と、記憶部に格納された演算値の経時変化を示す情報を表示装置に表示させるための処理を行う画像処理部と、を有する。