The route of degradation of sulfoxaflor in soil has been extensively determined. It was demonstrated that under aerobic conditions sulfoxaflor quickly degraded to its first major metabolite - X11719474. This process - hydrolysis of the terminal cyano-group to carbamino-group, was biologically mediated, what was confirmed by the experiment on sterilised soil. X11719474 then slowly degraded to X11519540, several other, non-identified metabolites, and terminally to CO2 and NER. The degradation of X11719474 was also biologically mediated, but, unlike the hydrolysis of sulfoxaflor which can be considered as partly abiotic process, the degradation of this compound was totally biologically-mediated process. On the basis of the results of the degradation of sulfoxaflor in soil under aerobic conditions the following metabolites are proposed to be considered major degradation products of sulfoxaflor: - X11719474, it met the criterion of the occurrence in soil in amounts >10% AR at any time point, being observed in max. concentration of 95-99% AR at DAT 1 in all soils; - X11579457, it met the criterion of the occurrence in soil in amounts >5% at two consecutive time points, in biologically viable sandy clay loam incubated at T=10°C it was observed at the following levels: 5.6-7.5% AR at DAT 62, 6.9% AR at DAT 90 and 5.8-6.6% AR at DAT 120; - X11519540, it met the criterion of the occurrence in soil in maximum amounts > 10% AR at any time point being observed in amounts 9.6-10.2% AR at DAT 46, 10.9% AR at DAT 81 and 9.6-12.2% AR at DAT 120 in biologically viable sandy clay loam soil incubated at 20°C, additionally it met the second criterion, occurrence in soil in amounts >5% AR at two consecutive time points, in the same soil incubated at both 20°C and 10°C.