In recent decades, antibiotics have been identified in the aquatic environment, raising serious concerns. This study demonstrates antibiotic degradation via a photocatalytic technique through novel TiO2 @MoS2/BiVO4 nanocomposites created using a simple hydrothermal method in the absence or presence of ultrasonic irradiation. Several approaches were applied to characterize the structural, morphological, electrical, and optical properties of the as-synthesized catalysts. It confirmed the successful heterostructure formation with superior properties compared to bare samples. Furthermore, tetracycline antibiotics were investigated for photocatalytic degradation. The results reveal that the TiO2 @ 2 M/8B (US) composite shows outperformance compared to other composites regarding photocatalytic activity toward tetracycline degradation. After five cycles, TiO2 @ 2 M/8B (US) and TiO2 @ 2 M/8B (NUS) exhibit sufficient stability for tetracycline degradation. Throughout the degradation process, superoxide and hydroxyl radicals were found to be the key active species. According to the results, TiO2 @ 2 M/8B (US) has much better catalytic activity than TiO2 @ 2 M/8B (NUS). The synergistic effect of ultrasonic irradiation and the TiO2 optical bandgap reduction by stacking BiVO4 and MoS2 is responsible for this remarkable photocatalytic improvement.