This study is to analyze why Russia continuously tries to construct the trans-Korean gas pipeline, despite the possibility of the “North Korean risk” and the limited economic benefit it offers compared to China's pipeline. As the world's number-one gas producer, Russia exports gas abroad through gas pipelines. As a result, Russia holds a wealth of expertise and experience related to gas pipelines. In particular, the crucial cases of gas pipeline disputes related to Russia since the collapse of the former Soviet Union mainly occurred during the Putin regime; the current President of Russia, Vladimir Putin, is trying to complete the trans-Korean gas pipeline. The content of the study is based on the above common ground. First, as Russia exports gas to various states through the gas pipelines, a great influence from its foreign policy standpoint is inevitable. Thus, this study will explore Putin's foreign policy of pragmatic realism. Second, the cause and effect of gas pipeline disputes concerning Russia during Putin's presidential term will be scrutinized with focus on Putin's pragmatic realism. Third, this paper will review the correlation between the results of cases of the gas pipeline dispute in relation to Russia and the gas market expansion in Russia's Northeast Asia. Lastly, this study will conceptualize the reasons for why Russia wishes to complete the trans-Korean gas pipeline based on these analyses.