A reagent selection support apparatus for supporting selection of a reagent used for cell measurement, comprising: a processing unit configured to acquire order information including a first measurement item and a second measurement item different from the first measurement item, and determine a combination of a first fluorescence reagent used to measure a first target molecule corresponding to the first measurement item and a second fluorescence reagent used to measure a second target molecule corresponding to the second measurement item, based on information on a property of the first target molecule and a property of a first fluorescent stain contained in the first fluorescent reagent, and information on a property of the second target molecule and a property of a second fluorescent stain contained in the second fluorescent reagent; and an output unit configured to output the determined combination of the first fluorescence reagent and the second fluorescence reagent, wherein the property of the first fluorescent stain is a value indicating an intensity of fluorescence from the first fluorescent stain and the property of the second fluorescent stain is a value indicating an intensity of fluorescence from the second fluorescent stain, and the property of the first target molecule is a value indicating an amount of the first target molecule present in the cell and the property of the second target molecule is a value indicating an amount of the second target molecule present in the cell, wherein the processing unit is configured to: determine the combination based on the value indicating an intensity of fluorescence from the first fluorescent stain, the value indicating an intensity of fluorescence from the second fluorescent stain, the value indicating an amount of the first target molecule, and the value indicating an amount of the second target molecule. a processing unit configured to acquire order information including a first measurement item and a second measurement item different from the first measurement item, and determine a combination of a first fluorescence reagent used to measure a first target molecule corresponding to the first measurement item and a second fluorescence reagent used to measure a second target molecule corresponding to the second measurement item, based on information on a property of the first target molecule and a property of a first fluorescent stain contained in the first fluorescent reagent, and information on a property of the second target molecule and a property of a second fluorescent stain contained in the second fluorescent reagent; and an output unit configured to output the determined combination of the first fluorescence reagent and the second fluorescence reagent, wherein the property of the first fluorescent stain is a value indicating an intensity of fluorescence from the first fluorescent stain and the property of the second fluorescent stain is a value indicating an intensity of fluorescence from the second fluorescent stain, and the property of the first target molecule is a value indicating an amount of the first target molecule present in the cell and the property of the second target molecule is a value indicating an amount of the second target molecule present in the cell, <EOS>