Heterojunction photocatalysts have shown considerable activities for organic pollutants degradation. However, the faint connection interface and inferior charge shift efficiency critically block the property of heterojunction photocatalysis. Herein, Bi₂O₂S/NiFe₂O₄ nanosheets heterojunction with ultrastrong interface interaction and high internal electric field are designed by an in-situ growth method. Tentative and theoretical consequences prove that the interfacial interaction and internal electric field not only act as the electron flow bridge but also decrease the electrons shift energy obstacle, thus speeding up electrons transfer and achieving effective spatial electron-hole separation. Therefore, a large amount of ·O₂^– and holes as active species were generated. Remarkably, Bi₂O₂S/NiFe₂O₄ establishes a considerably boosted photocatalytic performance for tetracycline degradation (0.032 min^–1), which is about 14.2-fold and 7.8-fold of the pristine BOS and NFO, respectively. This work provides a promising motivation for modulating charge transfer by interface control and internal electric field to boost photocatalytic performance.