Automated tape placement in large cylinder structure was studied with domestic T300/605 melting prepared prepreg. The ply angle was optimized to achieve the full scale laying in large cylinder structure,which would avoid the gap oroverlaps. On the basis of the optimization, the process experiment of large cylinder structure with automated tape placement was carried out and the result indicated that the adhesion of the prepreg tape was fit for automated tape placement.The gap or overlap between the tapes were less than 1mm and the error of ply angle was less than 0.2毅. Nondestructive testing of the composite cylinder and test of mechanical and physical performance was carried out.The result showed that the property of the composite cylinder was eligible,which indicated that automated tape placement satisfied the moulding of the large cylinder structure.