The invention discloses a determination method and device for the form of an electric transmission line. The determination method includes the steps that a first parameter is obtained, wherein the first parameter is the factor influencing the electric transmission line; a first preset algorithm is adopted to estimate the first parameter and obtain a first value corresponding to the first parameter; a second preset algorithm is adopted to estimate the first parameter and obtain a second value corresponding to the first parameter; the absolute value of the difference value is compared with the first preset value; the form of the electric transmission line is determined to be an overhead form when the absolute value of the difference value is compared to be larger than the first preset value and the first value is larger than the second value; the form of the electric transmission line is determined to be a cable form when the absolute value of the difference value is compared to be larger than the first preset value and the first value is smaller than the second value. According to the determination method, the problem that the form of the electric transmission line can not be determined quantificationally in the prior art is solved, and the effects of improving the reliability of the electric transmission line and reducing cost waste rate are achieved.