An object is to provide a channel-forming substrate capable of suppressing protrusion of a bonding adhesive while maintaining rigidity. The channel-forming substrate includes a first substrate in which a hollow portion to be a liquid channel is formed and a second substrate bonded to the first substrate with a bonding adhesive, in the first substrate, a plurality of first grooves are intermittently formed in a bonding surface bonded to the second substrate, in the second substrate, a plurality of second grooves are intermittently formed in a bonding surface bonded to the first substrate, and in a case where the channel-forming substrate is viewed from above, the first grooves and the second grooves are arranged alternately so as to surround the hollow portion.