Abstract:The reflection spectra of subaerial blue-green algae (Cyanophyceae) lack the reflected high peak of the reflected infrared spectral wave band (770--1000 nm)as usually exists in green seed plants. The curve of reflected ratio slopes gently. The reflected ratio of bluegreen algae growing on the mineral soil was positively correlated with the Mo concentration in the cells, and was evidently greater than that of the normal soil blue-green algae (13 %-- 27 %). This abnormal reflection ratio was related to the mineral concentration in soil. The reflection spectra of green algae (Chlorophyceae) and bryophyta were similar to these of the subaerial blue-green algae.