The research is dedicated to the investigation of the structure of the energy harvester with planar structure and its integration into the clothes. Electrodynamic converter consists of the set of flat, spiral-shaped coils and a block-shaped permanent magnet. During the human motions the generator elements move one relative to another and induce the pulses of voltage [2]. In order to increase the generator capacity, on the trajectory of the magnet movement several in series connected coils are located. Experimentally provides that the generated power reaches the maximum at the ratio of coil’s diameter D and the length of the magnet L, L/D is in interval 1.25 - 1.5 and the distance between the coils is equal to D / 2. By optimization of coils and magnet dimensions the mean power of into the jacket integrated prototype about 0.2 mW is obtained. With the planar coil geometry the generator minimal volume and occupied space are achieved, therefore power density of generator (about 1.8 mW/cm3) is higher than that proposed by other researchers [4], and it is suitable to be fully integrated into clothing.