To easily and correctly perform a butting operation between the termination of a preceding beltlike metal sheet and the start end of a succeeding beltlike metal sheet even in wide beltlike metal sheets.

A butt joining apparatus for beltlike metal sheets includes: a cabinet body 1 provided with a table 2 for work to be mounted with the preceding beltlike metal sheet W1 and the succeeding beltlike metal sheet W2; an upper clamp 4 holding the upper face of the termination part of the preceding beltlike metal sheet W1 and the upper face of the start end part of the succeeding beltlike metal sheet W2; a lower fixture 5 holding and fixing the vicinity of the butted parts of the preceding beltlike metal sheet W1 and the succeeding beltlike metal sheet W2 with the upper clamp 4; a center plate 6 performing the positioning of both beltlike metal sheets W1, W2; and welding equipment 8 butt-welding the butted parts of both beltlike metal sheets W1, W2. In the butt joining apparatus, the lower fixture 5 is provided with a workpiece clamp 7 holding and fixing the termination part of the preceding beltlike metal sheet W1 and the start end part of the succeeding beltlike metal sheet W2 to the upper face of the lower fixture 5 so as to be a close contact state.