Worldwide it can be clearly seen that the investment in electricity transmission and distribution infrastructures is very important for the power industry. The wind farm network structure means the combined electric power sources (wind turbine) and branching lines. Also, in a wind farm the branching lines are represented by cable underground power lines (cable). The approach presented in this paper was applied to optimize the electrical inter-array cable systems for wind farms which is compatible with both radial and branched design philosophies, and can optimize for total cable length or cable cost. The newness of the proposed approach is based on a combination of classical and met-heuristic algorithms that use graph theory for wind farm cable route optimization. The results of case study clearly demonstrated the feasibility of the proposed method and showed that it can be used as a reliable tool in off-shore wind farm design for optimal cable route determination.