To provide underwater placement equipment which enables a high-quality cement-based solidification material to be placed in a desired position even in a place with a flow.

The underwater placement equipment 1 is equipped with a placement pipe 2 which leads underwater concrete 7 to a lower end 22. The underwater placement equipment 1 comprises: a lower end supporting portion 3 which is attached to the lower end of the placement pipe in such a manner as to have an upper plate 31 having an insertion hole 31a for the insertion of the placement pipe formed, a lower plate 32 arranged in the state of facing the upper plate, and a connecting material 33 for connecting the upper and lower plates together at a predetermined spacing; a protrusion 4 which is provided on the peripheral surface of the placement pipe in an upper position, shorter than connecting material, from an end surface 22a of the lower end, and which is protruded sideward from the insertion hole in a projected view in the axial direction of the pipe; and a hydraulic jack 5 which is connected to the upper plate and the placement pipe in a position to be protruded above the lower end supporting portion, so as to move the placement pipe in the axial direction of the pipe.