Abstract: Transmission cables, which are not affected by natural conditions and good for urban aesthetics, high transmission safety and low maintenance cost, etc.,have gradually become the preferred alternative to urban overhead lines.However, traditional planning only considers the initial cost of the cable while selecting cables, less work have taken the cost of ventilation and heat dissipation during the cable operation into account.Aming at this lack of study, the selection method of transmission cable considering the annual investment operation cost is proposed, which is of great significance to reduce the comprehensive cost of cable engineering.