Fe

3

O

4

magnetic nanoparticles (MNPs) were synthesised

characterised

and used as a peroxidase mimetic to accelerate levofloxacin sono-degradation in an ultrasound (US)/H

2

O

2

system. The Fe

3

O

4

MNPs were in nanometre scale with an average diameter of approximately 12 to 18 nm. The introduction of Fe

3

O

4

MNPs increased levofloxacin sono-degradation in the US/H

2

O

2

system. Experimental parameters

such as Fe

3

O

4

MNP dose

initial solution pH

and H

2

O

2

concentration

were investigated by a one-factor-at-a-time approach. The results showed that Fe

3

O

4

MNPs enhanced levofloxacin removal in the pH range from 4.0 to 9.0. Levofloxacin removal ratio increased with Fe

3

O

4

MNP dose up to 1.0 g·L

-1

and with H

2

O

2

concentration until reaching the maximum.Moreover

three main intermediate compounds were identified by HPLC with electrospray ionisation tandem mass spectrometry

and a possible degradation pathway was proposed. This study suggests that combination of H

2

O

2

Fe

3

O

4

MNPs and US is a good way to improve the degradation efficiency of antibiotics.