Nowadays, in geotechnical engineering, laboratory investigations are necessary in order to assess their engineering properties, like stiffness characteristics. Knowledge about soil shear modulus (G) in a strain range of 1.0⋅10−4÷1% is very important to solve soil response subjected to dynamic loading. For purpose of that paper, shear modulus (G) of compacted sandy clay was measured in Water Centre – Laboratory, at Warsaw University of Life Sciences – SGGW by means of three different laboratory techniques, i.e., resonant column (RC), bender element (BE) and torsional shear (TS). Two methods of travel time identification in BE testing were applied: start to start (STS) and peak to peak (PTP). A brief description of these experimental techniques is given, with a special attention to strain level and excitation frequency they relate to. The main objective of this paper is to compare static against dynamic test results and monotonic against cyclic for cohesive compacted soil. In the next step, the behaviour of compacted sandy clay was compared with the behaviour of natural soil. The results suggest that in the case of BE measurements soil stiffness tends to be overestimated compared with stiffness obtained by RC and/or TS tests. The RC results are in good agreement with TS test results. The results received from the analyzed techniques indicate significant change in shear modulus with frequency and strain. The comparison of the results from different tests should be done at similar frequencies and referred to the same strain level. It is also shown that natural material is characterized by a greater stiffness than a compacted one.