Lysosomal cation test was applied to evaluation of nonspecific immune resistance in people exposed to small radiation doses. The surface dose over 5 mSv per year induced preservation or increase of cationic proteins. This state was not stable and later the concentration of cationic proteins tended to decrease. The subnormal granules were detected in the people exposed to radiation. The number of the granules depended on the level and time of exposure, so such subnormal granules can be considered a specific marker of radiation exposure. Prolonged simultaneous surface and interstitial radiation leads to the stable decrease of nonspecific immune resistance. Lysosomal cation test was proved to be one of the most acceptable methods for rapid mass evaluation of nonspecific immune resistance in people exposed to radiation.