Methane(CH_4) is one of important greenhouse gases with chemical activity. The determination of isotopic compositions for CH_4 emitted from the soils helps us to understand its production mechanisms. CH_4 isotope measurements have been conducted for different types of global terrestrial ecosystems. However, no isotopic data of CH_4 have been reported from Antarctic tundra soils. In this paper, ornithogenic soil profiles were collected from four penguin colonies, and potential CH_4 production rates and its 13 C ratio(δ~(13)C) were investigated based upon laboratory incubation experiments. The mean CH_4 production rates are highly variable in these soil profiles, ranging from 0.7 to 20.3 μg CH_4-C kg~(-1)?h~(-1). These ornithogenic soils had high potential production rates of CH_4 under ambient air incubation or under N2 incubation, indicating the importance of potential CH_4 emissions from penguin colonies. Most of the soil samples had higher δ~(13)C-CH_4 under N2 incubation(-39.28%~-43.53%) than under the ambient air incubation(-42.81%~-57.19%). Highly anaerobic conditions were conducive to the production of CH_4 enriched in 13 C, and acetic acid reduction under N2 incubation might be a predominant source for soil CH_4 production. Overall the δ~(13)C-CH_4 showed a significant negative correlation with CH_4 production rates in ornithogenic tundra soils under N2 incubation(R2=0.41, p<0.01) or under the ambient air incubation(R2=0.50, p<0.01). Potential CH_4 production from ornithogenic soils showed a significant positive correlation with total phosphorus(TP) and NH_4~+-N contents, p H and soil moisture(Mc), but the δ~(13)C-CH_4 showed a significant negative correlation with TP and NH_4~+-N contents, p H and Mc, indicating that the deposition amount of penguin guano increased potential CH_4 production rates from tundra soils, but decreased the δ~(13)C-CH_4. The CH_4 emissions from the ornithogenic soils affect carbon isotopic compositions of atmospheric CH_4 in coastal Antarctica. Methane (CH_4) is one of important greenhouse gases with chemical activity. The determination of isotopic compositions for CH_4 emitted from the soils helps us to understand its production mechanisms. CH_4 isotope measurements have been conducted for different types of global terrestrial ecosystems. However, no isotopic data of CH_4 have been reported from Antarctic tundra soils. In this paper, ornithogenic soil profiles were collected from four penguin colonies, and potential CH_4 production rates and its 13 C ratio (δ ~ (13) C) were subjected based upon laboratory incubation These mean CH_4 production rates are highly variable in these soil profiles, ranging from 0.7 to 20.3 μg CH_4-C kg -1 (-1) h -1. These ornithogenic soils had high potential production rates of CH_4 under ambient air incubation or under N2 incubation, indicating the importance of potential CH_4 emissions from penguin colonies. Most of the soil samples had higher δ ~ (13) C-CH_4 under N2 incubation (-39.28% ~ -43.53%) than under the ambient air incubation (-42.81% ~ -57.19%). Highly anaerobic conditions were conducive to the production of CH_4 enriched in 13 C, and acetic acid reduction under N2 incubation might be predominant source for soil CH_4 production. Overall the δ ~ (13) C-CH_4 showed a significant negative correlation with CH_4 production rates in ornithogenic tundra soils under N2 incubation (R2 = 0.41, p <0.01) or under the ambient air incubation 0.01). Potential CH_4 production from ornithogenic soils showed a significant positive correlation with total phosphorus (TP) and NH_4 ~ + -N contents, p H and soil moisture (Mc), but the δ ~ (13) C_CH_4 showed a significant negative correlation with TP and NH_4 ~ + -N contents, p H and Mc, indicating that the deposition amount of penguin guano increased potential CH_4 production rates from tundra soils, but decreased the δ ~ (13) C-CH_4. The CH_4 emissions from the ornithogenic soils affect carbon isotopic compositions of atmospheric CH_4 in c oastalAntarctica.