Provided are a voltage measurement method and apparatus. The method includes following steps: a number j of height values are selected in a vertical direction of a transmission line, a number m of sensors used for measuring, according to a Stark effect, electric field strength of a corresponding spatial position are arranged in sequence at each of j spatial positions of the j heights from the ground, electric field strength values of the corresponding spatial position are measured through the m sensors respectively, and an electric field strength average value of the corresponding spatial position is calculated according to the acquired m electric field strength values, where j and m are positive integers, and the j spatial positions are below the transmission line; a voltage of the transmission line is calculated according to j electric field strength average values.