Polyethylene film destruction by mixed culture of microorganisms was studied. The initial culture was adapted for growth on the media with ion exchange resin. During cultivation of the microorganisms on the mineral media with a polyethylene as the only source of carbon and energy the increase of film roughness and decrease of amorphous fraction and crystal size was detected. Using atomic-force microscopy and scanning electron microscopy it was found the film reduce to the crystals of micron size and unilamellar crystal fragments. The film relief change and crystal size decrease was detected after contact with oil-oxidizing bacteria and after composting with plant residuals with redworm Eisenia foetida.