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Trace fossils are important evidence of benthic activity and proxies of bottom and interstitial water oxygen content, making them a promising tool to understand the oceanic redox evolution and extinction patterns during the end-Permian mass extinction (EPME). Detailed bed-by-bed ichnologic studies were performed at a high-resolution scale from two uppermost Permian sections (Shangsi and Dongpan) in South China, documenting the presence of Chondrites targionii , Chondrites isp., Nereites isp., Planolites isp. A, Planolites isp. B, Palaeophycus isp., Phycosiphon incertum , Thalassinoides isp., and Zoophycos isp. The uppermost Permian strata at the Shangsi section mainly comprise siliceous limestone interbedded with illite-montmorillonite claystone and shale, recording a deep shelf setting. The uppermost Permian strata at the Dongpan section consist of mixed chert, mudstone and claystone, formed in a slope environment. Bioturbation index in uppermost Permian strata is mostly 1–2, but with thin intervals reaching 3–4. Fluctuating bioturbation intensities, ichnofaunal composition ( Thalassinoides , Planolites , Zoophycos ) and ethologies, as well as the ratio of highly reactive iron to total iron (Fe Hr/ Fe T ) and the proportion of the highly reactive iron pool in the form of pyrite (Fe py /Fe HR ) suggest that bottom and interstitial oxygen levels were not permanently anoxic/euxinic, but were interrupted by brief periods of aerobic conditions during the latest Permian. Three bioturbation phases in the EPME are identified. Phase I is characterized by the absence of typical pascichnia ichnotaxa (e.g. Nereites isp.) and relatively large fodinichnia burrow (e.g., Planolites isp. B; Zoophycos isp.). Phase II mainly consists of smaller Planolites isp. A, Thalassinoides isp. and Chondrites isp., recording a transition from softground to firmground. Only occasional smaller Planolites isp. A occur in Phase III without any associated vertical burrows. Ichnodiversity and bioturbation index from Phase I to Phase III show a step by step decline, corresponding to the two-stage extinction patterns. Long-term environmental stress (e.g., oceanic anoxia, volcanic winter, global warming, ocean acidification, hypercapnia) may have played major role in the collapse of the infaunal ecospace and only facies-crossing, highly tolerant, opportunistic organisms may have persisted in otherwise vacant ecological niches in the aftermath of the extinction. [ABSTRACT FROM AUTHOR]