An organic semiconducting copolymer according to example embodiments may be represented by Formula 1 below: An organic electronic device may include the above organic semiconducting copolymer. The organic semiconducting copolymer according to example embodiments may provide improved solubility, processability, and thin film properties. Consequently, the organic semiconducting copolymer may be used in a variety of electronic devices. A suitable electronic device may be an organic thin film transistor. When an active layer of an organic thin film transistor includes the organic semiconducting copolymer, higher charge mobility and lower breaking leakage current may be achieved.