The invention discloses a device and a method for measuring voltage of a noncontact charge induced high-voltage transmission line, and relates to an electronic sensor in the field of intelligent power grids. The device comprises a voltage testing sensor; the voltage testing sensor comprises an electric field sensor, a voltage correcting sensor, a data processing module and a signal output module, wherein the electric field sensor is used for acquiring electric field signals around the transmission line, the data processing module is used for receiving the electric field signals and converting the electric field signals into voltage signals, and the signal output module is used for receiving the voltage signals, processing the voltage signals and outputting the processed voltage signals to a display; and the electric field sensor comprises two hemispherical shell types electrodes and a measurement capacitor placed in a cavity formed by two hemispherical shells, and two polar plates of the measurement capacitor are connected with the hemispherical shell types electrodes respectively. Because the acquired signals are digitally transmitted, the precision is improved, the measuring range is wide, and saturation is not caused; and because the sensors are single-pole noncontact sensors, the installation is simple, the detachment is convenient, the volume is small, and great convenience is brought to construction and maintenance of the power grids.