Changes of morphometrical, biochemical, histochemical and immunohistochemical parameters were investigated in the alloxan diabetes in the dog. Samplings of material for electron microscopical and histochemical examinations were performed in 3 month period (4 times). A significant thickening of capillary basement membranes in the striated muscle (vastus lateralis) was ascertained even in the dog with glucose intolerance only. In this mentioned case a decrease of glucoso-6-phosphatase activity was observed. Evaluation of different types of muscle fibres assigned an increase of slow twitch fibres or intermediate ones respectively.