Photocatalyzed organic transformations have spurred immense interest in synthetic chemistry for the efficient conversion of solar energy into chemical energy. However, the crucial roles of support, which fixes catalytic sites and improves the light-harvesting ability, are often ignored in photoredox transformations. Herein, we report the utilization of spherical SiO₂ support to engineer AuPd alloy particles (denoted as AuPd/SiO₂), conceptually different from traditional methods for tuning optical absorption of plasmonic Au or AuPd particles, to manipulate light-harvesting ability of AuPd particles for highly selective and efficient photocatalytic Suzuki cross-coupling reactions. In this deliberately designed system, typically without the size and shape alternation of AuPd particles, the supported AuPd particles recycle the scattering light from spherical SiO₂ support and achieve the significant broad light-harvesting ability instead of the surface plasmon resonance peak. The engineered AuPd/SiO₂ composites by the use of near-field scattering-promoted optical absorption showcase the remarkably enhanced activity for visible-light-induced photocatalytic Suzuki cross-coupling reactions in comparison with that using commercial SiO₂ support, highlighting the spherical-support-effect induced efficient utilization of scattered light. This work highlights the feasibility of manipulating the light-harvesting capability of bimetallic particles by the near-field scattering-promoted optical absorption model toward efficient photo-driven Suzuki cross-coupling reaction and other C–C coupling organic synthesis to produce high value-added chemicals.