Current issues related to fuels can be grouped under four headings. Today world is facing three critical problems: (1) high fuel prices, (2) climatic changes, (3) air pollution, and [4] heating value. Higher Heating Value (HHV) is one of the most important properties of fuels which explain the higher energy content and determine the efficient use of biomass and fossil fuels. HHV comes to design calculations or numerical simulations of thermal conversion systems for fuels. There are numerous equations proposed in the literature for calculating the HHV of fuels from the basic analysis data. The proximate and ultimate analyses of fuels are necessary for their efficient and clean utilization while the HHV of fuels determine the quantitative energy content of fuels. The proximate analysis can be applied by using the simple lab equipments. The HHVs nine biomass samples were correlated with their lignin (L%) contents. There was a highly significant correlation between the HHVs and L% of the biomass samples. The HHV (MJ/kg) of the biomass sample as a function of the L was correlated using the following Equation: