This essay illuminates the political policies of Kim Doo-bong and the change of his position in North Korea’s politics of 1950’s. Kim Doo-bong was a nationalistic political exile and scholar which had nation-wide fame in the field of Korean language and history under the rule of Japanese imperialism. But this essay treated him as a ‘politician’. Kim Doo-bong entered the northern part of liberated Korea as a president of Korean Independence League(조선독립동맹) and soon became a key figure in North Korean politics. He played a leading role for the establishment of North Korean government in soviet occupied zone. And he took the lead for the establishment of North Korean constitution. As a result of it, he became a chairman of North Korean Supreme People Assembly’s standing committee(최고인민회의 상임위원회) in 1948 year, which was a ceremonial head of state in North Korea. During that time he has switched from a nationalist to radical democrat or a advocate of people’ democracy. But he endeavored to reinforce the influence of the Supreme People Assembly’s standing committee because he regards it as a symbol of South-North coalition(남북합작) by nation-wide united front. North Korean leadership assented to his intents and tends to respect the united front at the time of establishment government. However, after the outbreak of Korean war the situations changed. The wartime policy of Korean Worker’s party(조선로동당) was to seek a hegemony among the other political parties and social organizations. Kim Doo-bong has strived to maintain the constitutional power even in trouble with the leadership of the Korean Worker’s party though he belonged to the political committee. Particularly his efforts seemed to be supported by post-stalin soviet leadership. But, ultimately, his effort to maintain the political framework of people democracy constitution has failed in the aftermath of political conflicts which occurred around the central committee’ plenum of Korean Worker’s party in August, 1956 year. In a middle of nation-wide purge, Kim Doo-bong was brought down politically and in company with his downfall people democracy virtually came to an end.