The invention discloses an ultrasonic slotting and cutting tool. The ultrasonic slotting and cutting tool comprises a tool main body, wherein one end of the tool main body is provided with a positioning surface, a threaded section connected with an ultrasonic amplitude variation rod is arranged on the positioning surface, and a groove is formed in the other end of the tool main body; the groove comprises a conical groove bottom, a cylindrical hole and a frustum-shaped hole, wherein a horn-shaped cutting edge is formed by the frustum-shaped hole and the outer wall, away from one end of the positioning surface, of the tool main body, and a wrench groove is formed in the outer wall of the tool main body located between the positioning surface and the conical groove bottom; and at least one chip outlet which penetrates out of the outer wall of the tool main body is arranged at one end of the cylindrical hole close to the conical groove bottom, at least one inclined groove which penetratesout of the outer wall of the tool main body is formed in the inner wall of a hole section, close to the frustum-shaped hole, of the cylindrical hole. According to the machining tool, cutting force ofhoneycomb core slotting and cutting machining is reduced, so that the deformation damage of honeycomb core hole grids is effectively inhibited, and the machining quality and the machining precision are guaranteed.