The Bachelor's work is focused on issue of accuracy of measuring technologies applied in system GNSS in field and subsequently on comparison of them in the territory of borough Kováčová and Sielnica. There were simultaneously used 3 common mapping devices (IMU a GPS were compared with values derived from air laserscanning). In The Issue part there is a brief description of technologies and also principle of work and the conditions of behavior. In the part Plotting, based on the interpreted results, we deduced, that for more accurate localization and minimal deviations in localization, regarding route length, but especially altitude profiles (altitude) is necessary to use IMU, where result is precedented by standard deviation(2,024200041) of compared methods. Standard deviation of GPS is 8,122090771.