Herein, the novel solid solution (BiOBr)(x)(Bi7O9I3)(1-x) nanophotocatalysts with different x values (x = 0, 0.25, 0.5, 0.75 and 1) have been synthesized with an one-pot sono-solvothermal method to degrade the antibiotic levofloxacin, as an emerging pollutant, under simulated solar light. Moreover, to investigate the effect of microjets energy produced from ultrasound, the solid solution (BiOBr)(x)(Bi7O9I3)(1-x,) with optimum x, has been prepared using the one-pot solvothermal route. Synthesized products have been characterized by XRD, FESEM, HRTEM, EDX, BET-BJH, FTIR, DRS and pHpzc. It was found that (BiOBr)(x)(Bi7O9I3)(0.)(25)-U fabricated with the presence of ultrasound had the highest percentage in the 50 mg/L levofloxacin degradation, which was 95.4%. This result was assigned to its high activation in the solar spectrum range due to the band gap at around 2.43 eV, more effective charge transportation and separations, decrease in the recombination rate, large specific surface area (125.3 m(2)/g), great total pore volume (0.589 cm(3)/g) and also uniform dispersion and increased nucleation owing to the presence of ultrasound energy, which has led to an increase in the catalytic active sites. Also operational parameters such as the photocatalyst loading, concentrations of pollutant and pH of solution were investigated. Furthermore, the reaction mechanism was suggested for levofloxacin photodegradation.