A composite fiber component for a rotor blade of a wind power plant including a first sandwich core and a second sandwich core arranged next to each other, each having an inside facing a rotor blade interior and an outside facing a rotor blade exterior. A first fiber-containing laminate layer is arranged on the inside of the first sandwich core and on the outside of the second sandwich core. A second fiber-containing laminate layer is arranged on the outside of the first sandwich core and on the outside of the second sandwich core. And, a third fiber-containing laminate layer is arranged on the inside of the first sandwich core and on the inside of the second sandwich core. Also disclosed is a rotor blade for a wind power plant having a composite fiber component as disclosed.