Langmuir-Blodgett films of four polymers containing benzoate and cinnamate main chains and Disperse Red 19 in the side chains were prepared and characterized by means of BAM and AFM. The poly(para-benzoate) and poly(para-cinnamate) gave LB films with much higher ordered textures than the respective meta-polymers. The para-polymers apparently possess self-assembly capacity, and this is thought to be the cause of their high second order nonlinear optical susceptibility. The X-type films of the para-polymers showed second order nonlinear optical responses, suggesting that the para-polymers form self organized membranes with the chromophores orientated to the direction perpendicular to the substrate.