Flexible organic films are important functional materials with a wide range of applications in many areas such as electronic devices and packaging. However, some organic films have shortcomings such as insufficient hydrophilicity, poor biocompatibility, and low chemical reactivity. Introducing hydroxyl functional groups through surface treatments can enhance the hydrophilicity of organic films, and improve their properties and functions, making them more suitable for various application fields. This study conducted dry and wet hydroxylation treatments on the surfaces of flexible organic films to investigate the impact of hydroxylation processes on their hydrophilicity. The results indicated that when the wet hydroxylation treatment time and temperature were increased, the water contact angle on the organic film surface initially decreased and then stabilized. In contrast, when the plasma treatment time was increased, the water contact angle first decreased and then increased. Additionally, the water contact angle of a surface treated with dry hydroxylation was approximately 20° lower than that treated with wet hydroxylation, resulting in better hydrophilicity of the organic substrate and a shorter processing time.