This scientific article investigates the impact of various storage conditions on the physicochemical properties of three types of agro-biomass pellets: sunflower husks, wheat straw and hemp hurds, and wood pellets. The experiments were conducted in a climatic chamber that simulates real-world storage environments, including high air humidity and fluctuating ambient temperatures. The findings revealed a higher degradation rate in agro-biomass pellets than in woody biomass.