Dinitrate compounds was prepared from alkane diols; 1,6-hexane diol, 1,8-octane diol, 1,10-decane diol, and 2-methyl-2,4-pentane diol using nitration reaction. These dinitrate compounds were used as cetane improver for diesel fuel. Results showed that the cetane number values has increased about 1 and 3 units for 0.05 and 0.10% by weight of dinitrate compounds, respectively, compared with base oil. Their efficiency is higher than commercial cetane improver, 2-ethylhexyl nitrate.