The invention provides a surveying instrument, which comprises a frame unit provided capable of rotating horizontally via a horizontal rotation shaft, a telescope unit provided capable of rotating vertically via a vertical rotation shaft in a recessed portion formed in the frame unit, a vertical rotation driving unit in which a vertical output shaft is connected to the vertical rotation shaft, and a whirl-stop unit provided on an outer side of a side plate of the frame unit along the side plate and connecting the vertical rotation driving unit and the frame unit to each other.