A belt splicing apparatus includes: a mold including a cavity into which connecting end portions of a resin-made belt are inserted, opposing each other, to connect the end portions by using a bonding resin; a heating unit that heats a bonding resin to more than a flow starting temperature of the bonding resin; and a pressure maintaining unit. The pressure maintaining unit includes: a reservoir communicating with the cavity and maintaining the bonding resin in a fluid state; a pressure transmitting member that transmits pressure to the bonding resin in the fluid state; an urging unit that urges the pressure transmitting member; and an urging force adjusting unit that adjusts an urging force applied by the urging unit.