The objective of the paper was to evaluate the influence of variable humidity conditions, especially dynamic water absorption from air, on the extrudated products. The material used for the research was the wheat - corn extrudate processed in a double-screw extruder. During the storage in the climatic chamber three factors influenced the investigated samples: temperature, relative humidity and the storage time. It was found that extrudates were characterized with considerable sensibility on variable conditions of the storage. Rapid growth of the absorbed humidity mass, particularly in the initial hours of the storage in the climatic chamber was reported.