The invention discloses a light induced chemiluminescent immunoassay reagent kit for aflatoxin B1and a detection method thereof, which belong to the technical field of light induced chemiluminescent immunoassay. A luminescent particle enveloped with AFB1-BSA is added into a microporosity plate, a AFB1 standard or sample, a rabbit anti-AFB1 antibody, a biotin goat anti-rabbit antibody are sequentially added for a photophobic reaction, then a photosensitive particle enveloped with streptavidin is photophobically added, and the mixture is incubated and then is detected. The AFB1-BSA enveloped on the luminescent particle competes with the AFB1 in the standard or sample for connecting to the AFB1 antibody to form a complex with the biotin goat anti-rabbit antibody and the photosensitive particle enveloped with the streptavidin, the energy is transferred to the luminescent particle to produce fluorescence by producing and transferring singlet ionic oxygen under optical excitation, a light induced chemiluminescent detector is used to detect, the intensity of optical signals is inversely proportional to the concentration of the AFB1, and the content of the AFB1 in the measured sample is determined by contrasting with the standard curve. The invention is used to detect the content of the AFB1 in foodstuff, feedstuff and products of the foodstuff and the feedstuff; and the reagent kit has the advantages of simple structure, simple and convenient operation, low cost, short detection time, and high sensitivity.