The methacrylate monomers bearing mesogenic group and heterocyclic azo dye have been synthesized. The monomeric dye was copolymerized with the mesogenic monomer using a free radical initiator to produce polymers useful for nonlinear optics. The monomers and polymers were characterized by IR, 1H-NMR, and UV-Vis spectra. The average molecular weight(Mw and Mn)of the polymers were determined by gel permeation chromatography. The thermal properties of the polymers such as thermal stability and phase transition behavior were studied by thermogravimetric analysis, differential thermal analysis, polarizing optical microscope and X-ray diffractometer. The results demonstratethat the synthesized polymers are crystalline polymers at room temperature and no liquid crystalline phases were observed for all of them.