A method of manufacturing a liquid discharge head includes: forming a first hole which penetrates through a wafer and becomes at least part of a liquid supply port and a second hole which does not penetrate through the wafer and becomes at least part of a cut-off portion from a front side of the wafer; arranging a dry film on the front side of the wafer; forming a flow passage forming member by heating and developing the dry film; and cutting off the liquid discharge head from the wafer by grinding the wafer from a back side so that the second hole penetrates through the wafer.