The experiments were made on 22 rabbits with induced single or recurrent renal colic. Ten animals after renal colic were exposed to magnetolaser radiation. The histological examination of renal tissue demonstrated colic-related changes both in renal body corpuscle and ductules. Parenchimal edema, parabiotic processes in epitheliocytes and even necrosis of some cells were found. In case of recurrent colic the changes were severe, much more epitheliocytes were damaged, inflammatory leucocyte infiltration appeared. Magnetolaser radiation reduces the damage, eliminates leucocyte infiltration. Lymphocytic infiltrates formed in renal interstitium after two sessions of magnetolaser therapy indicate stimulation of cell immunity. The same processes develop also in the contralateral kidney. Their activity depends on the number of colics. Therefore, magnetolaser radiation has a protective action both on the isolated organ and body as a whole.