Overhead transmission line generally use ACSR conductor type (Aluminium Conductor Alloy Reinforced), it has makimum temperature allowable is 90oC. To take into consideration of electric demand increasing recently, then effort to expand of transmission line capacity with develop new transmission, however need the high cost. ACCR conductor (Aluminium Conductor Composite Reinforced) has been developed recently. The superiority of this conductor is resist to the heat until 240oC, hence current carrying capacity higher than ACSR conductor. This research aimed to study load current leading to mechanical performance characteristic ACCR conductor included tension, length of elongation and sag of conductor, hence expected from this research will be useful to develop construction structure of transmission line appropriate to characteristic of ACCR conductor. Based on this research it can be concluded that application of ACCR conductor improves transmission line capacities by 100 % on existing ROW and tower.