Abstract: By means of calorimetry measurement, the caloric value (CV), the standing crop of energy (SCE), the net energy production (NEP) and energy conversing efficiency (ECE) of total radiation in vascular aquatic macrophyte (VAM)communities were determined and discussed. The results showed that (1) The average CV of the VAM was 15.39 kJ/gDM, the CV in stems and leaves was generally higher than in roots; and the CV of emerged plants> CV of floating plants > CV of submerged plants. (2) The CV of the floating plant communities were similar to that of emerged ones, and both were bigger than that of submerged ones. (3) The SCE was the highest in emerged plant communities, and the lowest in floating ones, while the submerged communities had a intermediate SCE. The vertical allocation of the SCE accumulated in the submerged communities could be divided into three types. (4) The ECE of total solar radiation by VAM communities was 0.54% in average, among which the ECE of Phragmites communis community was the highest (2.09%)and the average ECE of submerged communities was 0.26%.