The graduation thesis discusses the comparison of different GNSS survey methods for the determination of small displacements of points in a geodetic network. Firstly, the theoretical basics of GNSS technology operation, the characteristics of GNSS methods and the procedure for the determination of displacements are presented. In the main part, the practical use of GNSS methods for detecting small point displacements is described. Moreover, the whole procedure for measuring small displacements is introduced - from fieldwork, measurement processing and computation of point displacements to test statistics. The comparison of different GNSS methods has been made for static, kinematic and RTK method by performing point displacements of the selected point in the geodetic network, from 1 to several cm and from 1 to 3 mm. Position of the selected point has been computed relatively to different reference stations. Point displacements have been determined in three different ways; according to initial position of selected point, as a difference between consecutive positions and according to the difference between average positions. Furthermore, the computation of the accuracy of displacements and the computation of test statistic, which could be used for the advanced analysis of displacements and consists of the size and the standard deviation of the discussed point displacement, has been presented.