It was developed the method for determining the strength of material without breaking the test sample. The essence of the method is to determine the strength characteristics of the rock by pressing into the variable cross-section indenter. The practical significance lies in the possibility of performing an express analysis of the strength of rocks on small-sized samples - 3 mm or more, for example, using the particles of landslide cuttings from unstable intervals when drilling wells; there is no need for the preparation of reference material; the simplicity and availability of the equipment used and high accuracy of the results obtained is also important. The developed method has no analogues and is patented in the patent offices of the Republic of Belarus and the Russian Federation.