The aim of the research was to determine how long Wet Brewers‘ Grains (WBG), preserved without any additives, can be stored in a bag with a capacity of 25 tons. The WBG were in 2015 and in 2016 stored more than 3 months in the bag. After opening the bag was determined one week aerobic stability. The fermentation and aerobic degradation was continuously monitored by measuring the temperature and chemical analyzes, and in 2016 also microbial analyzes. Results from 2016 confirmed those of 2015. If the WBG still warm tipped out of a truck directly into the bag and anaerobically it closed, it can keep free of preservatives even 3 months. After opening the bag the number of yeasts and molds significantly increased after 7 days. Quality of stored WBG more negatively affected the access of air than the length of storage.