The progress of contemporary nanolithography techniques allowed one to structure media on submicron scale. Varying the geometry of the structuring makes the media acquire different optical properties which are not specific to the host media. Among the most remarkable properties are magnetic response of nanostructures at optical frequencies and negative refraction [1], extraordinary optical transmission [2], light nanofocusing with nanostructured metallic films [3], artificial optical anisotropy [4] and chirality [5]. The latter two have become possible with thin metallic films structured with patterns of certain type of asymmetry. Nevertheless the thickness of the films are much less than the wavelength of visible light, these metamaterials are capable of competing with conventional bulk polarization optics in specific linear birefringence and dichroism [4] and chirality [5]. In this work different types of anisotropic metamaterials are considered and the crucial role of surface plasmon-polariton excitation is established. Two samples of anisotropic meteamaterials were fabricated using electron-beam lithography out of 30 nm-thick golden film situated on the fused silica substrate. The first sample contained periodically packed nanowires with cross-section of the single wire being 30x100 nm2. Linear transmission coefficient spectrum demonstrates no peculiarities if the polarization of the incident light is parallel to the wires and a 100 nmwidth dip is seen on the spectrum for orthogonal polarization indicating the local plasmon-polariton (LPP)resonance at λ = 570 nm. The second sample consisted of an array of nanoslits with the width of 80 nm each. This sample is shown to maintain the propagation of surface plasmon-polaritons (SPP) which possess much narrower transmission resonance of about 15 nm when the incident wave’s E-field is directed perpendicular to the slits. Both samples’ periodicities were 300 nm which is about 2 times less than the typical light’s wavelength at which large optical anisotropy is observed. The samples demonstrated vast polarization transformation capabilities. Polarization plane rotations up to 90° and elliptizations up to 1 (linearly polarized light “in,” circular polarized light “out”) are observed in the vicinity of SPP and LPP resonances. Phase delays between linearly polarized eigenstates of the samples up to 0.13π for LPP sample and 0.85π for SPP sample are obtained. To compare these results with conventional bulk anisotropic media, the latter phase delay value could be delivered by a 30-nm-thick medium with ΔnE10 while the most uniaxial crystals have birefringence of Δn<0.2 only. The birefringence of the plasmon-active medium could be tuned by adjusting the geometry of the experiment, i.e. the angle of incidence. It is shown that for certain wavelength the birefringence Δn of the SPP sample is changed from 0.5 to 10 by tuning the angle of incidence from 30° to 50°. It is shown that it is possible to cover the whole polarization Poincaré sphere with the states output from the sample when the incident state is fixed. Along with its extremely low thickness this abilies favorably distinguish these metamaterials from bulk anisotropic crystals making them a promising object for modern telecommunication technologies.