Ultra-intense electromagnetic fields exceeding 10²³ W/cm² are enabling breakthroughs in compact laser-driven particle accelerators and revealing new quantum electrodynamics (QED) phenomena. However, conventional laser focusing methods face considerable engineering challenges and require substantial costs. Focusing schemes utilizing plasma optics can produce sub-micrometer focus spots beyond the diffraction limit and substantially enhance peak intensity; however, owing to significant energy dissipation, they may fail to simultaneously increase the laser fluence. To address these challenges, we propose a novel focusing scheme employing a near-critical-density hollow plasma fiber (HPF) that utilizes graded refractive index dynamics to simultaneously boost both laser peak intensity and fluence. Three-dimensional particle-in-cell (PIC) simulations demonstrate the HPF’s capability to focus a 4.5-μm-diameter Gaussian beam to a sub-diffraction-limited 0.6-μm-diameter spot. The peak intensity and laser fluence can be enhanced by factors of 22 and 10, respectively, marking a substantial improvement over existing plasma-based focusing schemes. Furthermore, the proposed scheme exhibits wide-range parameter adaptation and high robustness, making it suitable for direct implementation in PW-class ultra-intense laser experiments.