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Combining heterojunction with advanced structures is a promising tool to enhance the photoelectrochemical performance of semiconductor photocatalysts for environmental remediation. Herein, a novel multi-heterojunction TiO 2 @Bi 2 O 3 (MHTB) hollow photocatalyst is successfully constructed by loading Bi 2 O 3 nanoparticles on the surface of inner TiO 2 and outside of TiO 2 shell. Photoelectrochemical characterizations show that the formation of multiple heterojunctions at the TiO 2 @Bi 2 O 3 interfaces facilitates faster separation and transfer of photoinduced charge carriers than that of conventionally reported p-n heterojunction photocatalysts. Because of the separated two layers of Bi 2 O 3 and unique hollow structure, the photocatalytic performance of MHTB is significantly improved, leading to excellent photo-degradation rate constant (k = 0.0165 min−1) for the degradation of levofloxacin, which approaches 1.5-fold and 2.6-fold increase than that of TiO 2 @Bi 2 O 3 @TiO 2 (n-p-n heterojunction) and TiO 2 @Bi 2 O 3 (n-p heterojunction), respectively. Notably, the MHTB photocatalyst exhibits an excellent anti-interference capability for the interference of environmental factors. Moreover, the photocatalytic activity, crystal structure, and bonding energy of MHTB photocatalyst remain unchanged after being used several times, indicating an excellent stability. Therefore, this finding opens a new door to develop highly active photocatalysts with multiple heterojunctions for efficient pollutant removal and environmental remediation. [Display omitted] • Multi-heterojunction TiO 2 @Bi 2 O 3 photocatalyst (MHTB) was prepared for the first time. • MHTB drove the efficient degradation (>98%) and mineralization (92.6%) of levofloxacin under visible light. • Multi-heterojunction and hollow structure contributed to the degradation of levofloxacin. • The degradation pathway and mechanism of levofloxacin was proposed. [ABSTRACT FROM AUTHOR]