This invention relates to the use of axial substituted phthalocyanine compound as a semiconductor layer between the source/drain electrodes of organic thin-film transistor. The centre ligand of the axial substituted phthalocyanine compound is an atom with 3 valences or higher, and the axial ligands are chlorine, fluorine, or oxygen which can be connected with the centre ligands of axial substituted phthalocyanine compounds. Crystalline Film with high quality can be prepared on an organic substrate from the axial substituted phthalocyanine compound using vapor deposition process. These crystalline films have high carrier mobility, rich energy level, and stable performances and are easy for integrated process. The field effect mobility and the on/off Ratio of the organic thin-film transistor are 0.01 cm2/Vs or more and higher than 105, respectively.