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Flexible supercapacitors hold promise for applications in wearable electronic devices. However, the challenges of achieving flexibility, miniaturization, and high volumetric capacitance persist. In this work, precise laser etching of cellulose composites, prepared via in-situ growth of conductive metal–organic frameworks (c-MOFs) on cellulose nanofibers (CNF), was employed to fabricate flexible, binder-free, and integrated microsupercapacitors (MSCs). The interfacial synthesis of Ni₃(HITP)₂ (a type of c-MOF) on the surface of CNF yields a continuous and uniform conductive shell, enabling efficient electron transfer along the CNF@c-MOF nanofibers. The interwoven structure of the nanofibers creates a hierarchical porous network with enhanced surface area featuring interconnected porous channels, enabling rapid ion transport. The laser etching technique facilitates one-step production of integrated MSCs with a precisely interdigitated configurations and micron-scale accuracy. The fabricated MSCs demonstrate excellent mechanical stability, with a tensile strength of up to 81.9 MPa, and remarkable flexibility, maintaining consistent electrochemical performance under bending stress. The flexible device, with a thickness of only 45 µm, achieves a high volumetric specific capacitance of 36.7 F cm⁻³ at a current density of 0.17 mA cm⁻² and a specific energy density of 2,497.5 µWh cm⁻³ at a power density of 53.3 mW cm⁻³. This study provides a new strategy for designing flexible, binder-free, integrated MSCs with high capacitances and long cyclic stability, demonstrating significant potential for applications in wearable electronics.