The heat of polymerization DeltaH(p), of nitropropyl(meth)acrylate monomers has been studied by differential scanning calorimetry (DSC) in dynamic and isothermal modes. DSC showed that DeltaH(p) of 2-nitropropyl(meth)acrylate was surprisingly smaller than that of propyl(meth)acrylate but similar to that of 2,2-dinitropropyl(meth)acrylate. According to molecular structure analysis by a PM3 Hamiltonian in a MOPAC program, the contributing main factor to the lowering of DeltaH(p) of 2-nitropropyl (meth)acrylate was found to be the hydrogen bond between the O(=C) and the H atom attached at position C6.