Ivermectin (IVM) is a widely used antiparasitic agent and acaricide . Despite its high efficiency against nematodes and arthropods, IVM may pose a threat to the environment due to its ecotoxcity . In this study, degradation of IVM by a newly isolated bacterium Aeromonas taiwanensis ZJB-18,044 was investigated . Strain ZJB-18,044 can completely degrade 50 mg/L IVM in 5 d with a biodegradation ability of 0.42 mg/L/h . Meanwhile, it exhibited high tolerance (50 mg/L) to doramectin, emamectin, rifampicin, and spiramycin . It can also efficiently degrade doramectin, emamectin, and spiramycin . The IVM degradation of strain ZJB-18,044 can be inhibited by erythromycin, azithromycin, spiramycin or rifampicin . However, supplement of carbonyl cyanide m-chlorophenylhydrazone, an uncoupler of oxidative phosphorylation, can partially recover the IVM degradation . Moreover, strain ZJB-18,044 cells can pump out excess IVM to maintain a low intracellular IVM concentration . Therefore, the IVM tolerance of strain ZJB-18,044 may be due to the regulation of the intracellular IVM concentration by the activated macrolide efflux pump (s). With the high IVM degradation efficiency, A. taiwanensis ZJB-18,044 may serve as a bioremediation agent for IVM and other macrolides in the environment.Electronic supplementary material: The online version of this article (10.1007/s10532-020-09909-8) contains supplementary material, which is available to authorized users.