The invention relates to a high-voltage switch. The high-voltage switch comprises a housing, a positive electrode, a negative electrode and a trigger electrode, wherein the positive electrode and the negative electrode are oppositely arranged in the housing, the trigger electrode is arranged between the positive electrode and the negative electrode and is provided with a guide hole in a shape of a circular truncated cone, the small-mouth position of the guide hole is located on one side of the negative electrode, the large-mouth position of the guide hole is located on one side of the positive electrode, the top end of the negative electrode is inserted into the guide hole through the small-mouth position, and the housing is full of inert gas. The trigger electrode comprises a trigger piece and a reinforcing piece attached to one side of the trigger piece, and guide holes are formed in the trigger piece and a reinforcing piece which attach to each other. The invention further provides a shock wave stone breaker and a shock wave therapeutic apparatus using the high-voltage switch. The using times of the high-voltage switch can be increased, accordingly the service life of the high-voltage switch is prolonged, and the manufacturing difficulty and costs are further reduced. In addition, the shock wave stone breaker and the shock wave therapeutic apparatus using the high-voltage switch are also long in service life.