The second-order nonlinearity of poled-polymer during photobleaching process is monitored with second harmonic generation(SHG) intensity enhanced by surface plasmon resonance(SPR) in an attenuated total reflection (ATR) configuration. The nonlinear coefficient d33 of the poled polymer is determined by comparing the SPR enhanced second harmonic generation(SHG) intensities with that from the calibrated quartz. Experimental results show that photobleaching process has less effect on the second-order nonlinearity of a poled cross-linked polymer than that of a poled side-chain polymer.