The work aimed to study the patterns of cavitation-erosion destruction of steels and titanium alloys. Electrochemical measurements were carried out on an installation with a magnetostrictive vibrator using the technique of potentiostatic measurements. Polarization curves were recorded at a constant temperature of 296 K under static conditions and with the application of ultrasonic vibrations for steels and a group of titanium alloys. The research was carried out using sodium chloride solutions. Tests were also carried out in hard water to obtain comparative data. A new approach was proposed for assessing the cavitation-erosion resistance of various metals and alloys. It consists of analyzing polarization curves obtained under static conditions, applying ultrasonic vibrations, and comparing them with the results of corrosion tests. It was established that high corrosion resistance, in combination with the strength characteristics of titanium alloys, provides high cavitation resistance in sodium chloride solutions. During electrochemical studies, an increase in the speed of anodic processes under all modes of cavitation influence and a narrowing of the area of passivation of the studied materials were established. All the metals tested in NaCl solutions and hard water can be conditionally divided into three groups. For the manufacture of equipment parts prone to cavitation-erosive wear in sodium chloride solutions, it is recommended to choose materials from the 3rd group and primarily titanium and its alloys.