Organic polymer materials have been broadly applied in optical storage, optical communication and optical signal process. It has been revealed that these organic materials have some superior characteristics such as larger electro-optical (EO) coefficients, broader bandwidth and shorter response time, which make it good for EO modulator application. In our study, the goal is to study the EO coefficient of novel polymer material to be used in low driving voltage EO modulator. During the experiment, the dependence of the second harmonic generation (SHG) intensity on doping concentration of DR1/PMMA was observed and a reasonable explanation of the nonlinear dependency was given. We measured the EO coefficient of a new material, ASF/PMMA, using a Mach-Zehnder interferometer. We also observed the relaxation process of SHG intensity of this new material, which was compared with that of DR1/PMMA. Under the same measurement condition, we found that the EO coefficient of ASF/PMMA (13.1 pm/V) is significantly larger than that of DR1/PMMA (3 pm/V). It is also found that relaxation time of ASF/PMMA and DR1/PMMA are 22 and 8.5 seconds, respectively. Because of the superior characteristics of this material, it is suitable to be used in EO modulator.