Polymer system in their diversity may offer a range of alternative, especially in the form of suitably designed thin films. Thin films made of so-called polymer brush show unique properties that allow changing their topography between different morphologies. Mixed polymer brushed consisting of two homopolymers (polymethyl methacrylate and polystyrene) being covalently with one end to a solid substrate have attached abiding interest because of their ability to switch properties such as the surface energy and/or surface topography in response to challenge of their environment.[1] For this reason, a conventional microscopic technique (AFM or STM) cannot provide information on specificity of biomolecular interaction.A near field microscope incorporating vibrational spectroscopy as a contrast mechanism would allow chemical mapping in the so called “fingerprint region”, with the high spatial resolution of SNOM [2-4]. Using a scattering scanning near-field microscope (s-SNIM) allows us to simultaneously record topography and frequency-dependent near-field signal of organic and biological samples with sub-diffraction limited resolution of up to 90 nm [4]. For chemical imaging of surface patterns in mixed polymer brushes, we used two tunable lasers, a CO laser (4.8μm - 6.3μm) and a high power continuous wave infrared optical parametric oscillator (OPO) (3.2μm - 4.1μm) as radiation source. We performed measurements around 1740 cm-1 (C=O stretching mode of methyl methacrylate) and 2930cm-1 (C-H stretching mode of styrene). An advanced image processing of the topography and the near-field image provided the evaluation of frequency dependent contrast showing spectroscopic signature.[1] S. Santer, Macromolecules, 39, 3056-3061, 2006[2] L. Novotny, S. Stranick, Annu.Rev.Phys,Chem, 57, 303-331, 2006.[3] B. Dragnea, Encyclopedia of Nanoscience and Nanotechnology, Dekker, 2703-2712, 2004.[4] B. Knoll, F. Keilmann, Nature, 399 (6732), 134-137, 1999.[5] I. Kopf et. al. J.Phys.Chem. C, 111, 8166-8171, 2007.