A railcar bogie (100, 200) comprising: a cross beam configured to support a carbody of a railcar the cross beam extending through a railcar width direction middle portion of the bogie in the left-right direction; wheels arranged at both railcar width direction sides of the bogie (100, 200) to be lined up in a railcar longitudinal direction at each of the sides; a pair of front and rear axles between which the cross beam is located and which are respectively arranged at a front side and rear side in the railcar longitudinal direction so as to extend in a railcar width direction, each of the axles connecting the wheels located at a left side and right side in the railcar width direction; bearings arranged at both railcar width direction sides of each of the axles and configured to rotatably support the axle; axle box portions coupled to the cross beam via elastic members and each configured to store one of the bearings; and plate spring portions extending in the railcar longitudinal direction so as to respectively support both railcar width direction end portions of the cross beam, both railcar longitudinal direction end portions of each of the plate spring portions being respectively supported by the axle box portions, and each of the plate spring portions having a longitudinal direction middle portion having the same distance from both railcar longitudinal direction end portions of the respective plate spring portion, wherein each of the axle box portions includes a supporting surface that supports the plate spring portion such that the plate spring portion and the supporting surface are movable relative to one another, and wherein the supporting surface is, considered in a side view parallel to the railcar width direction, inclined toward the longitudinal direction middle portion of the plate spring portion. a cross beam configured to support a carbody of a railcar the cross beam extending through a railcar width direction middle portion of the bogie in the left-right direction; wheels arranged at both railcar width direction sides of the bogie (100, 200) to be lined up in a railcar longitudinal direction at each of the sides; a pair of front and rear axles between which the cross beam is located and which are respectively arranged at a front side and rear side in the railcar longitudinal direction so as to extend in a railcar width direction, each of the axles connecting the wheels located at a left side and right side in the railcar width direction; bearings arranged at both railcar width direction sides of each of the axles and configured to rotatably support the axle; axle box portions coupled to the cross beam via elastic members and each configured to store one of the bearings; and plate spring portions extending in the railcar longitudinal direction so as to respectively support both railcar width direction end portions of the cross beam, both railcar longitudinal direction end portions of each of the plate spring portions being respectively supported by the axle box portions, and each of the plate spring portions having a longitudinal direction middle portion having the same distance from both railcar longitudinal direction end portions of the respective plate spring portion, wherein each of the axle box portions includes a supporting surface that supports the plate spring portion such that the plate spring portion and the supporting surface are movable relative to one another, and wherein the supporting surface is, considered in a side view parallel to the railcar width direction, inclined toward the longitudinal direction middle portion of the plate spring portion.