A hydraulic brake apparatus, comprising: a housing, wherein the interior of the housing is a cavity structure, and the cavity structure communicates with the outside; a first piston, disposed in the cavity structure inside the housing, wherein the first piston and the housing form a first cavity; a baffle plate, disposed in the first cavity and dividing the first cavity into a first sub-cavity and a second sub-cavity, wherein the first sub-cavity is formed by the housing, the first piston, and the baffle plate, and the second sub-cavity is formed by the first piston and the baffle plate; a second piston, disposed in the cavity structure inside the housing and located outside the first cavity, wherein the second piston, the first piston, and the housing form a second cavity; and a first elastic component, a second elastic component, and a third elastic component, disposed in the first sub-cavity, the second sub-cavity, and the second cavity respectively and configured to slide the baffle plate, the first piston, and the second piston in the cavity structure inside the housing when the second piston is subjected to an external acting force, wherein the housing comprises a first through hole and a second through hole, wherein the first through hole is disposed in a first position of the housing, the second through hole is disposed in a second position of the housing, the first position is a position in which the second piston can slide in the cavity structure inside the housing, and the second position is a position in which the first piston can slide in the cavity structure inside the housing; the second piston comprises a third through hole, wherein when the second piston slides to the third through hole and is coupled to the first through hole, the second cavity communicates with the outside; or when the second piston slides to the third through hole and is staggered from the first through hole, the second cavity is isolated from the outside; and the first piston comprises a fourth through hole and a fifth through hole, wherein the fourth through hole is disposed in a third position of the first piston, the fifth through hole is disposed in a fourth position of the first piston, the third position is a position that is of the first piston and that constitutes the first sub-cavity, and the fourth position is a position that is of the first piston and that constitutes the second sub-cavity; and when the fourth through hole and/or the fifth through hole are/is coupled to the second through hole, the first sub-cavity and/or the second sub-cavity communicate/communicates with the outside; or when the fourth through hole and/or the fifth through hole are/is staggered from the second through hole, the first sub-cavity and/or the second sub-cavity are/is isolated from the outside. a housing, wherein the interior of the housing is a cavity structure, and the cavity structure communicates with the outside; a first piston, disposed in the cavity structure inside the housing, wherein the first piston and the housing form a first cavity; a baffle plate, disposed in the first cavity and dividing the first cavity into a first sub-cavity and a second sub-cavity, wherein the first sub-cavity is formed by the housing, the first piston, and the baffle plate, and the second sub-cavity is formed by the first piston and the baffle plate; a second piston, disposed in the cavity structure inside the housing and located outside the first cavity, wherein the second piston, the first piston, and the housing form a second cavity; and a first elastic component, a second elastic component, and a third elastic component, disposed in the first sub-cavity, the second sub-cavity, and the second cavity respectively and configured to slide the baffle plate, the first piston, and the second piston in the cavity structure inside the housing when the second piston is subjected to an external acting force, wherein the housing comprises a first through hole and a second through hole, wherein the first through hole is disposed in a first position of the housing, the second through hole is disposed in a second position of the housing, the first position is a position in which the second piston can slide in the cavity structure inside the housing, and the second position is a position in which the first piston can slide in the cavity structure inside the housing; the second piston comprises a third through hole, wherein when the second piston slides to the third through hole and is coupled to the first through hole, the second cavity communicates with the outside; or when the second piston slides to the third through hole and is staggered from the first through hole, the second cavity is isolated from the outside; and the first piston comprises a fourth through hole and a fifth through hole, wherein the fourth through hole is disposed in a third position of the first piston, the fifth through hole is disposed in a fourth position of the first piston, the third position is a position that is of the first piston and that constitutes the first sub-cavity, and the fourth position is a position that is of the first piston and that constitutes the second sub-cavity; and when the fourth through hole and/or the fifth through hole are/is coupled to the second through hole, the first sub-cavity and/or the second sub-cavity communicate/communicates with the outside; or when the fourth through hole and/or the fifth through hole are/is staggered from the second through hole, the first sub-cavity and/or the second sub-cavity are/is isolated from the outside.