This paper presents the method to solve the transmission line parameters calculation problem with computer program. The transmission line parameters are an important of power system which calculates the voltage current power and other. Transmission line parameters program is programmed with Delphi in graphical user interface. This program can calculated the resistance inductance and capacitance of single and three phase transmission line. To verify the performance of the proposed program the results are compared with the manual method. The results show that the program method is able to obtained 100 percent accuracy