The main factors influencing the emitting characteristics of longtime afterglowing pigments are briefly discussed. The essential requirements for measuring the emitting characters are introduced. A new apparatus satisfied for the measurement of longtime afterlowing pigments is developed. It uses D 65 simulator as the stimulating source and uses auto-range photometer to measure luminance of longtime afterglowing pigments. The light from stimulating source to the pigment sample and the emitting light from the pigment sample to the photometer are transmitted by optical fibres. The stimulating light is controlled by an electric shutter which is coupled between the two optical fibres. The apparatus operated by a computer. It would be specially mentioned that the apparatus can be operated under the normal lighting condition. The measurements shows design of the apparatus is very ingenious and practical.