A split seal ring includes: an annular main body seal split partially in a circumferential direction; and abutment surfaces provided on split surfaces of the main body seal so as to be joined to each other. Each of the abutment surfaces includes: a first inclined surface extending in a direction intersecting with the circumferential direction; a first horizontal surface extending from one end side of the first inclined surface along the circumferential direction; and a second inclined surface extending from an end of the first horizontal surface opposite to the first inclined surface in the direction intersecting with the circumferential direction. With this configuration, there can be provided a split seal ring having a structure that can improve the sealing performance.