The energy dynamics in Thiashola grassland, a montane subtropical vegetation in Nilgiri Biosphere Reserve, the Western Ghats, India is studied for a period of one year. The study revealed that the energy content in unit biomass of C3 and C4 species has not varied significantly. However, the C4 species in total due to higher net primary production, entrapped 8.5 times greater solar energy (28.82 kcal/m2/day) than that of their C3 counterparts. Of the total energy fixed, the C3 and C4 species, respectively channeled 4.07 kcal/m2/day and 13.3 kcal/m2/day to the aboveground standing live compartment. The transfer rate of energy to standing dead compartment from standing live part were 3.22 kcal/m2/day and 10.36 kcal/m2/day for C3 and C4 species, respectively and both the C3 and C4 together transferred 4.81 kcal/m2/day of energy from standing dead to litter compartment. The total dissipation of energy from the system is determined to be 4401.11 kcal/m2/yr and the surplus quantity of 38.37% of energy is accumulated in the aboveground parts of both C3 and C4 species which indicates the availability of substantial amount of energetic fodder to the wild herbivores in the Thiashola grassland.