Abstract: With the increase of power transmission capacity,the transmission corridor problem is becoming more and more prominent,especially,expropriation of land,compensation for green seedlings,house demolition and other costs account for an increasing proportion of project investment,and the implementation is difficult.Taking Longcheng-Chaijiazhai 220 kV power transmission and transformation project as an example,the 220 kV and 500 kV mixed-voltage double-circuit F-type narrow-base tower of the same tower is studied,and three schemes are designed in the study. The data such as local scheme sample drawing,environmental conditions and selection of ground conductor are compared,and Scheme Three is recommended.