A measurement method for the deposition amount of spray, using tracer and spectrophotometer was developed. Food colors was selected as tracer, because it was cheep and easily treatable. Using NIRS(Near Infrared Reflection Spectrophotometer), regression curves between absorbance spectrum and concentration of the tracer were obtained. Yellow food colors showed the peak of spectrum at 452nm, and absorbance of peak showed a tendency to increase as concentration increased. Also, the possibility of concentration control by heating was investigated.