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尾瀬ヶ原は日本最大の高山泥炭湿原であり，貴重な泥炭生態系として保全されてきた．しかし20世紀後期からニホンジカの侵入と豪雨による洪水による生態系の攪乱が顕在化してきた．本稿では二酸化炭素（CO2）やメタン（CH4）放出に関する既往の研究と尾瀬ヶ原湿原におけるニホンジカの攪乱が及ぼす影響を概観する．尾瀬ヶ原，中田代の5か所，14地点で2019年6～10月の5か月間に土壌およびガス試料を採取・分析した．攪乱によるアンモニア態窒素の増加が認められた．非攪乱地のCO2やCH4放出は8月に極大が見られ攪乱地より多かった．CO2やCH4放出量は地下水位と負の相関関係が見られ，尾瀬ヶ原におけるニホンジカの攪乱が地下水位と泥炭土壌の理化学性および温室効果ガスの放出に顕著な影響を及ぼしていることが示された．, Ozegahara mire is the largest alpine mire in Japan. The mire has been preserved as a precious peatland ecosystem with high ecological diversity. After the late 20th century, the mire has been exposed to ecosystem disturbance by mire flooding due to heavy rain as well as invasive Sika deer. This manuscript reviewed studies about greenhouse gas emission from wetland and report the effects of Sika deer disturbance on the soil physicochemical properties and the emission of carbon dioxide (CO2) and methane (CH4) from Ozegahara mire. Soil and gas samples were collected at fixed 14 fixed plots on 5 sites with and without mire disturbance by Sika deer in Naka-tashiro of Ozegahara mire through 5 months of 2019 (June to October), and determined their properties and gas composition each month. Groundwater level displayed similar seasonal change in two sites, being affected by precipitation. The concentrations of NH4+ nitrogen in the disturbed sites were higher than those in the undisturbed sites. Mechanical disturbance of the peat soils by deer resulted in mineralization of organic matter. CO2 and CH4 fluxes from the undisturbed sites were highest in August, and those were higher than those from the disturbed sites. Negative correlation was found between CO2 and groundwater level and also correlation between CH4 and groundwater level was negative, suggesting the importance of groundwater level in greenhouse gases flux, depending on the sites and also species of greenhouse gases.