Control the photocatalytic activity by texturing morphology and surface property is the fundamental and efficient process for the advanced applications of semiconductors. In this work, high-performance flower-like BiOCl (BOC) nanomaterials were fabricated employing sustainable cellulose nanofibrils (CNFs) as regulator through a facile one-pot hydrothermal method. The CNFs doped BiOCl (CBOC) formed flower-like morphology and the size was decreased. Ascribing to the enhanced photosensitization and photocatalysis, RhB could be totally degraded by CBOC-5 (5% of CNFs) within 16 min under visible light irradiation, exhibiting outstanding degradation efficiency. The roles of adsorption, photosensitization and photocatalysis of CBOC-5 to RhB and tetracycline (TC) were comprehensively studied. The O-center dot(2)- and holes were determined to be the active species during the RhB degradation in the presence of CBOC-5 under visible light irradiation and CBOC-5 showed excellent stability after 5 times repeated use. The crucial role of CNFs for the improved photocatalytic activity was mainly attributed to forming flower-like morphology, reducing the size of BOC and enhancing the hydrophilic surface, as a result, the absorption of visible light, migration of electron and the interaction of CBOC-5 with RhB were promoted remarkably, which enhanced both photosensitization and photocatalytic activity significantly.