This investigation was aimed to estimate the influence of low-intensive laser irradiation at a constant magnetic field in case of experimental renal colics. The research was made on twenty rabbits where a single or recurrent colic increased. Ten animals after a single colic underwent laser therapy. Results of histological examination (hematoxylin-eosin coloration, magnification 400) showed changes coming up (in renal body corpuscle, as well as in ductules). Parenchymal odoema, parabiotic processes in epitheliocytes and even necrosis of single cells were found. In case of recurrent colics changes were severe, much more epitheliocytes were damaged, and even inflammatory leucocyte infiltration appeared. When laser therapy has been used pathologic processes were not so expressed. Leucocyte infiltration was not found. In the intestinal tissue lymphocyte infiltration was a consequence of cellular immunity improvement resulting from quantum irradiation influence. A similar process occuring in the contralateral kidney depended on the number of colics and, laser therapy showed its protective effect in this group. The received results proved the protective influence of the laser therapy in case of struck kidney and even on an organism in a whole.