The galactic space between the stars is filled with the interstellar medium. This matter is permeated with magnetic fields and it consists of atomic, molecular and ionized gas, cosmic rays and dust. From the aspect of radio astronomy, interstellar medium is best investigated by detection of synchrotron radiation, which is also called non-thermal radiation.The observation of synchrotron radiation in the frequency range of 100 to 200 MHz with LOFAR radio telescope in 2015 discovered a flat filamentary structures in 3C196 field that rotate the plane of polarization of background synchrotron radiation. Their origin is still unknown, but it is assumed that the filamentary structure is probably caused by an ionized filament in the ISM, located at about 100 pc away from us. As the 3C196 field is located in a region that is dominated by numerous HI filaments, a comparison of LOFAR polarization maps with EBHIS observations of neutral hydrogen was made in 2016. The research has shown that HI filaments are best seen at the velocity of -5 km / s. The aim of this thesis is to show at what Faraday’s depth of LOFAR’s P-rm cube and EBHIS HI cube velocity correlates the highest. The comparison was made in two ways, visually using the SAOImage DS9 program and determining Rayleigh statistics using the AstroHOG tool. Both methods show that there is good alignment between the images and the correlation is the highest for a pair of channels on which Faraday’s depth is 1.5 rad / m 2 and the speed of -6.34 km/s. The amount of Rayleigh’s statistics for the given combination is 450.06 so it turns out that the orientation directions in the images are parallel. Since the amount of the mean resultant vector is approximately equal to zero, there is not only one dominant matching path in the images. This comparison ultimately showed extremely good alignment between LOFAR and EBHIS data, which further confirms Kalberl’s thesis that LOFAR filaments in polarized emission and HI are related to each other and that the 3C196 field is the ideal target for discovering their common characteristics.