Using an ultra-weak bioluminescent image detecting system, the delayedluminescent (DL) images of Excoecaria cochinchinnensis leaves and some other plantspecies are detected. The results show that the DL can offer the important information of photosynthesis, cell division and energy transformation of plant species.Chlorophyll plays an important role in the plant DL. However cell division alsohas some influence on DL. The measured photon count rate after light illuminationcan be approximated by a hyperbolic decay law, which supports coherence theory.Whereas, two-exponential law also accords with measured data, which shows thatDL perhaps comes from two photosystems in plant cells and each of them gives achaotic luminescence after induced by light.