MXenes, a new class of two-dimensional materials with excellent performance, are promising materials for wearable energy storage devices. However, the lack of sufficient interaction between various MXene particles makes it difficult to translate the exceptional performance from the nanoscale to macroscale. Additionally, the intrinsic characteristic of easy oxidation limits their practical applications. Herein, inspired by the structure of wood, a biomimetic core-shell MXene@graphene oxide (MX@GO) fiber was fabricated using GO as a mechanical layer to wrap MXenes. The GO layer could easily assemble MXene particles into macroscale materials and protect them from oxidation. Therefore, the as-fabricated core-shell MX@GO fiber showed a high tensile strength (290 MPa) and excellent electrical conductivity (2400 S m-1). Notably, the conductivity of the biomimetic fiber only decreased to 1800 S m-1 with a reduction of about 30% at 100 °C. This work paves the way to fabricate MXene-based fibers with freely designed functionalities and morphologies, which are suitable for various high-value fabric-based applications.