Abstract: A guide instrument for passing a medical needle with thread through or between body tissues has first and second shafts mounted to be pivotally movable to each other and is formed with, on the first shaft, a needle stand for making the needle with thread stand up and holding the needle with thread, a hole for guiding the thread, and a slit and with, on the second shaft, a needle receiver for receiving the needle when the shafts are made close while the needle with thread stands up at the needle stand. When the shafts 1, 2 are made close while the needle with thread stands up at the needle stand, the needle with thread passes through and between the body tissues and is engaged with the needle receiver. When the shafts are made open, the needle with thread while keeping the engagement with the needle receiver separates from the needle stand, and therefore, the needle with thread can be guided from the first shaft to the second shaft.