An organic semiconductor material, enabling to exhibit liquid crystal phase at wide temperature range including at least ordinary temperature and to exhibit high charge carrier mobility, and an organic semiconductor structure and organic semiconductor device formed from the organic semiconductor material. The organic semiconductor material has a quaterthiophene skeleton as shown in a following chemical formula 1, wherein R1 in the chemical formula 1 is an alkyl group of C1 to C20 or a hydrogen, and R2 is an alkyl group of C1 to C20 or a hydrogen.