The article presents the results of studies of cavitation and solid particle erosion resistance of samples of 20GL and 30L steels with various surface modification options based on nitriding and boriding processes. Tests for cavitation resistance were carried out according to the ASTM G134-17, and for solid particle erosion resistance - according to the ASTM G76-13. It was revealed that to increase wear resistance, the depth of modification of the considered steels should be at least 80 microns. Based on the totality of cavitation and solid particle erosion studies carried out, the best option for surface modification for 20GL steel is boriding, and for 30L steel nitriding.