The mechanism of some enzyms taking part in the degradation of grain polysaccharides during the initial period of triticale germination is discussed. This concerns the function of the high pI α-amylase which is suggested to be the most important isoform active in the starch hydrolysis as well as the 1-3, 1-4-β-glucane-4-glycosidase which seems to be one of the most important enzymes degrading the cell wall structural components – β-glucanes. The use of two triticale varieties differentiated in their susceptibility to pre-harvest sprouting allowed to discuss both the enzyme activities and the internal structure changes evidenced in the light and electron microscope in relation to the various processes taking part in those samples. Most interesting observations seem to be those concerning the aleurone layer where the characteristic channels and perforations in the cell wall were formed specially in case of samples demonstrating the elevated activities of β-endoglucanase. Similar effects od starch digestion were observed in samples where the high pI-α-amylase isoform was present. Microscopic observations on the loosening of the cell wall structure seem to be particularly interesting as this could be the mechanism facilitating the enzyme and metabolite translocation through the grain tissues, thus accelerating the metabolic processes.