Disclosed are compositions for forming organic insulating films and methods for forming organic insulating films using one or more of the compositions. The compositions include at least one ultraviolet (UV) curing agent, at least one water-soluble polymer and at least one water-soluble fluorine compound, and the method includes applying the composition to a substrate to form a coating layer, irradiating the coating layer with UV light to form an exposed layer and developing the exposed layer with an aqueous developing solution to obtain an organic insulating film and/or pattern. Also disclosed are organic thin film transistors comprising an organic insulating film formed by one of the methods using one of the compositions that may exhibit improved hysteresis performance and/or acceptable surface properties without the need for additional processing, thereby simplifying the fabrication process.