Kortowski cheese (M nster type) was salted for 100, 75, 50 and 25% of their standard salting time, which is 48 hours. Cheese after 3 weeks of ripening and cheese immediately after salting were stored for 6 and 12 months at -27°C. Cheese of lower salting level ripened faster, both after salting and after frozen storage. The process of protein degradation occurred during frozen storage of ripe cheeses. The content of N-amino acid in ripe cheese after frozen storage and in cheese ripening after storage was almost twice as high as in the cheese that ripened after salting. Separations on Sephadex gel confirm the process of protein degradation during frozen storage of cheese. The conducted research indicated that frozen storage is recommended for Kortowski cheese of reduced salt content and the most favourable solution is to conduct the process of cheese ripening after thawing.