Introducing amine functional groups on polymer surfaces is extremely important for studying various processes that involve polymer surfaces. We report a novel and extremely simple method for preparing a tertiary-amine-terminated poly(ethylene terephthalate) (PET) surface by using a UV-light-induced surface aminolysis reaction. X-ray photoelectron spectroscopy and attenuated total-reflection infrared spectroscopy give direct evidence of the incorporation of tertiary amine functionalities and the possible reaction mechanism behind this technique. Tertiary amines are easily protonated, so we have developed an extremely simple method for immobilizing and patterning biomolecules on a soft surface by the electrostatic self-assembly of proteins, such as immunoglobulin (IgG) and horseradish peroxide (HRP), onto a patterned, aminated surface. An enzyme-substrate reaction, which is followed optically by observing the resulting precipitation on the surface, is used to reveal the patterned immobilization of HRP, where 3-amino-9-ethylcarbazole, as a substrate for HRP, is deposited on the aminated surface after HRP adsorption. Fluorescein isothiocyanate-labeled lgG (FITC-IgG) has been immobilized electrostatically onto the ordered aminated spots, and the fluorescence intensity ratio of the IgG-immobilized region (inside the spot) to the background (outside the spot) is about 5:1, as calculated from a fluorescence image and fluorescence spectra obtained by microlaser confocal Raman spectroscopy. We have found that the background intensity is mainly caused by the autofluorescence of virgin PET, and after subtracting this value from the measured intensity inside and outside the spot, respectively, a much higher intensity ratio between the spot and the background is obtained (about 22:1). The patterned immobilization of FITC-IgG has been further proven by examining the change in intensity inside the spot after photobleaching the fluorophore.