The preparation of poly(ethylene oxide) (PEO) films of different molecular weights was carried out by casting the films from aqueous solutions of different concentrations, where the optimal conditions for dissolving the polymer in water were investigated. Successfully prepared solutions were subjected to drying, with the aim of finding optimal drying conditions, i.e. the process of preparing quality dry films. Differential scanning calorimetry (DSC) was applied to investigate the influence of different molecular weights, film thicknesses and drying temperatures in a vacuum dryer on the thermal properties and crystallinity of PEO. The formation of different PEO crystals was observed in the investigated films, and it can be said that certain thermal characteristics of the films doesn’t differ significantly. The thermal stability of the films was investigated using non-isothermal thermogravimetry (TG). PEO films are digested in one stage of decomposition and there is no difference in the superior film stability due to the influence of different drying temperatures in vacuum drying, different molecular weights and concentrations of polymer solutions. The main goal of the research related to the successful removal of solvents from films has been achieved.