To determine the pole and tower position for transmission line in mountainous areas, weight span/wind span (Kv) is one of the important limiting factors of pole and tower. While designing transmission line in mountainous areas, there are often cases where the weight span and wind span are not large enough, and the Kv value is small, which can be solved raising tower height, adopting a tower with a smaller Kv value, or adopting a tension support as breaking measure. The three methods above will increase the engineering quantity, and a newtype inverted “Y” string transmission tower is introduced to solve this problem. It can be used in the areas with small Kv. In the case of strong wind, ice coating, broken wire and other working conditions, the stress of the insulator is analyzed, and reasonable design of fitting strings is proposed. The finite element model is established, and the natural vibration coefficients are obtained and compared with that of conventional towers. Based on the time domain method, the distribution characteristics of wind vibration coefficients are studied, and the recommended values of the wind vibration coefficients for tower bodies and cross arms of inverted “Y” tower are put forward. Finally, the comparative analysis of the economic performance of the inverted “Y” string tower is carried out. Through the research, the electrical and structural characteristics of the inverted “Y” towers are revealed, and the results can be used as a reference for the design of transmission towers.