Disclosed is a liquid processing apparatus that includes: a rotational unit configured to rotate a substrate to be processed while the substrate is being held horizontally; and a processing liquid supplying unit configured to supply a processing liquid to the bottom surface of the substrate to be processed which is rotating. The rotational unit includes an enclosing member surrounding the periphery of the substrate to be processed, the enclosing member includes a plurality of guide grooves formed on the bottom surface of the enclosing member and configured to guide the processing liquid, and each of the plurality of guide grooves elongates outwardly from the inner periphery and is arranged in the circumferential direction of the enclosing member.