A flush toilet bowl includes a bowl part, a rim nozzle, and a rim water spout part. The bowl part has a rim part on an upper edge of a receiving surface with a bowl shape. The rim nozzle is provided on a rear part of the bowl part and spouts flush water. The rim water spout part is provided on the rim part and spouts flush water that is spouted from the rim nozzle toward the receiving surface. The rim water spout part includes a rim water guide channel that is formed inside the rim part and guides flush water that is spouted from the rim nozzle and a rim water spout port that is formed to be continuous with the rim water guide channel and in a front side region of the bowl part. The rim nozzle spouts flush water upward in the rim water guide channel.