A new 3D flexible biosensor based on rGO nanocomposites was developed for noninvasive sweat glucose detection. In this work, researchers developed a noninvasive and flexible 3D glucose biosensor for sweat analysis, which requires high sensitivity and detection limits. The biosensor was fabricated using rGO nanocomposites assembled onto SiO2 nanospheres via electrostatic interaction and reduced by tannic acid (TA). The biosensor was fabricated using rGO/SiO2 nanocomposites, glucose oxidase, and Nafion solution on a conductive substrate, forming a 3D electroactive structure to increase the sensing and recognition sites. The NF/GOx/rGO/SiO2/C-PDMS biosensor exhibited a sensitivity of 60.8 μA mM -1 cm -2 and a low detection limit of 3.7 μM, superior to existing sensors, for detecting glucose in the range of 0.1-9 mM. The 3D structure of the biosensor also exhibited excellent anti-interference performance, stability, and accuracy in detecting glucose from sweat samples. This new biosensor offers a promising strategy for developing wearable sensors for real-time glucose detection.