Presence of antibiotics in water is persistent, bio accumulative and harmful to humans and aquatic habitats hence the need to find ways of their removal. This study investigated the catalytic degradation of rifampicin using iron oxide nanoparticles synthesized using aqueous extracts of Galinsoga parviflora, Conyza bonariensis and Bidens pilosa. The effect of temperature, pH, time, and adsorbent dose on the rate of degradation were evaluated by carrying out the reaction in different reaction conditions. From the results obtained in this study, the percent degradation was found to be dependent on the pH, temperature, and the amount of the nanoparticles used during the study. Higher degradation efficiencies were obtained when the degradation was studied in acidic media as compared to basic and neutral media and when the temperature and the amount of the nanoparticles used were 60 ℃ and 20 mg, respectively. The degradation of rifampicin using iron oxide nanoparticles was found to be pseudo second order, endothermic and dependent on the reactants used during the study and variation of reaction conditions led to an increase in the percent degradation observed. In conclusion, iron nanoparticles synthesized using Galinnsoga parviflora, Conyza bonariensis and Bidens pilosa could be used catalytically in the presence of hydrogen peroxide to degrade rifampicin in aqueous media.