The invention relates to a switch component for a direct-current breaker and the direct-current breaker. The switch component comprises switch power modules, each of the switch power modules comprisesa first bridge arm and a second bridge arm, which are connected in series, as well as a capacitance valve group and at least two fully controlled device valve groups; the first bridge arm and the second bridge arm are both formed by connecting two uncontrolled device valve groups in series in the same direction; the switch component further comprises a front-row uncontrolled device valve segment,a fully controlled device valve segment and a rear-row uncontrolled device valve segment which are successively arranged at intervals along the front-and-back direction, in each switch power module,the uncontrolled device valve groups in the first bridge arm and the second bridge arm are connected in the front-row uncontrolled device valve segment in a pressed mode, the uncontrolled device valvegroup in the lower bridge arm is connected in the rear-row uncontrolled device valve segment in a pressed mode, and the fully controlled device valve groups are connected in the fully controlled device valve segment in a pressed mode. By symmetrically arranging the front-row uncontrolled device valve segment and the rear-row uncontrolled device valve segment on two sides of the fully controlled device valve segment, the switch component not only has a compact structure and is high in modularization degree but also is convenient for assembly and wiring.