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Lipid biomarker abundances and δ¹³C values were determined across the Permian–Triassic (P–Tr) boundary at Meishan of southern China. The δ¹³C values of n-alkanes showed large (∼9‰) fluctuations, which suggest major episodic changes in oceanographic conditions during faunal mass extinctions. Environment-related biomarker ratios, including pristane to phytane ratios (Pr/Ph), gammacerane to C₃₁ homohopane ratios (γ/C₃₁HP) and C₂₇ 18α(H)-22,29,30-trinorneohopane to C₂₇ 17α(H)-22,29,30-trinorhopane ratios (Ts/Tm), vary extensively throughout the section, with values typically associated with anoxic conditions coinciding with maximum δ¹³C values. In particular, both faunal mass extinction horizons (beds 25 and 28) are characterised by biomarker ratios consistent with anoxic conditions and elevated n-alkane δ¹³C values. The records of environment-related biomarkers and n-alkane δ¹³C …