Abstract Transmission and transformation project is related to the national economy and people’s livelihood, and its development and construction level is directly related to the national life happiness. The full development of computer technology has brought good news to many fields, and the construction of power transmission and transformation projects has also benefited deeply. This paper probes into the application of computer technology in the field of power transmission and transformation engineering cost analysis, points out the three difficult problems it faces, and gives the corresponding solutions.