This study investigates the degradation of tetracycline using dual-frequency ultrasound (DFUS) combined with peroxymonosulfate (PMS). The research highlights the effectiveness of this combination in degrading tetracycline, which is a harmful substance widely used in aquaculture, livestock production, and human therapeutics. The study compares the degradation rates under different conditions, finding that DFUS combined with PMS achieved a degradation rate of 64.2% after 60 minutes, significantly higher than the individual effects of either method alone. The main reactive radicals involved in the degradation process were identified as O2-, SO4-, and •OH. The number of active bubbles in the degradation vessel was calculated, showing a higher value of 1.44 × 10^14 L^-1 s^-1 when using DFUS at 20 kHz (210 W/L) and 80 kHz (85.4 W/L). The combination of DFUS and PMS was found to enhance the generation of reactive free radicals and mass transfer processes, leading to efficient removal of tetracycline from wastewater. The study also assessed the toxicity of tetracycline and its intermediates, finding that the combination of DFUS and PMS significantly reduced the toxicity of the treated solution. The results provide a promising method for the treatment of tetracycline in wastewater.This study investigates the degradation of tetracycline using dual-frequency ultrasound (DFUS) combined with peroxymonosulfate (PMS). The research highlights the effectiveness of this combination in degrading tetracycline, which is a harmful substance widely used in aquaculture, livestock production, and human therapeutics. The study compares the degradation rates under different conditions, finding that DFUS combined with PMS achieved a degradation rate of 64.2% after 60 minutes, significantly higher than the individual effects of either method alone. The main reactive radicals involved in the degradation process were identified as O2-, SO4-, and •OH. The number of active bubbles in the degradation vessel was calculated, showing a higher value of 1.44 × 10^14 L^-1 s^-1 when using DFUS at 20 kHz (210 W/L) and 80 kHz (85.4 W/L). The combination of DFUS and PMS was found to enhance the generation of reactive free radicals and mass transfer processes, leading to efficient removal of tetracycline from wastewater. The study also assessed the toxicity of tetracycline and its intermediates, finding that the combination of DFUS and PMS significantly reduced the toxicity of the treated solution. The results provide a promising method for the treatment of tetracycline in wastewater.