In this article,CIGS thin films were d eposited on glass substrates by three-stage co-evaporation technique,and the i nflu ence of substrate temperature of deposited precursor layer on structural propert ies of CIGS thin films is researched.The thickness,the composition,the crystal structure,the morp hology and the electical properties of the films were measured by step meter,X-ray diffraction (XRD),sca nning electron microscope (SEM) and Hall meter respectively.Ga content in precursor layers is lower,and I n₂Se_3phase is more easily formed for lower substrate temperatures (for 300℃ and 360℃).Ga content in precursor layers is higher,and (In,Ga)₂Se_3phase is more easily formed for higher substrate temperature (f or 400℃).The reason is that formation enthalpy of Ga₂Se₃(－462.4kJ/mol) is lower than that of In₂Se ₃(－360kJ/mol),and In₂Se_3phase is stabler than Ga₂Se_3phase under low temperature especially.When substrate temperatur es are higher,Ga₂Se_3phase is easy to be formed,and is made up of (In,Ga)₂Se_3and In₂Se_3phases.Furth ermore,Ga content in CIGS thin films deposited under higher substrate temperature (for 400℃) is higher than that under lower temperature,and the coarseness and resistivity of CIGS films are lower,while the mobility and th e carrier density of CIGS films are higher.