The invention provides a high temperature superconductivity power device low temperature high voltage partial discharge experiment and test device in a horizontal structure. A low temperature vessel (18) is cylindrical and is horizontally arranged. Two insulating terminals (13) are vertically welded at the upper part of the low temperature vessel (18). Two low temperature high voltage bushings (1) are respectively vertically arranged on two insulating terminals (14) through a flange and a supporting metal voltage-sharing ring (3). The lower ends of two low temperature high voltage bushings are respectively inserted into two insulating terminals (14). A liquid nitrogen infusion tube inlet (11) and a liquid nitrogen infusion tube inlet (13) are respectively arranged on the side walls of two insulating terminals (14). Two exhaust systems (5) and two measuring lead outlets (12) are respectively arranged on the side walls of two insulating terminals (14). Two manholes (9) are respectively located on both ends of the low temperature vessel (18).