Sugawara family served the court as a scholar from generation to generation. He had a great talent for studying and poetry since he was a child. He was given important posts by Emperor Uda[宇多天皇（うだてんのう）](867-931). Michizane abolished Kentōshi[遣唐使（けんとうし）](Japanese missions to Tang China) in 894 when he was appointed to its ambassador because of the confusion of China.
Emperor Uda passed the throne to Emperor Daigo[醍醐天皇（だいごてんのう）] in 897 but Michizane also continued to be promoted in the reign of Emperor Daigo and he was appointed to Udaijin[右大臣（うだいじん）](minister of the right) in 899. Udaijin was the most important governmental post in the court after Dajyōdaijin[太政大臣（だじょうだいじん）](grand minister) and Sadaijin[左大臣（さだいじん）](minister of the left). These posts were commonly given to the relatives or descendants of imperial family mainly such as Fujiwara[藤原（ふじわら）] clan. That was the extraordinary promotion for Michizane.
But in 901, Michizane was relegated to the head of Dazaifu[大宰府（だざいふ）] by a false rumor that he planned to let the emperor abdicate. This incident is called "Shōtai no Hen[昌泰の変（しょうたいのへん）]". Dazaifu was the office governing Kyūshū Region that was located in now Dazaifu[太宰府（だざいふ）] City, Fukuoka Prefecture and it was definitely his demotion. It is said that this incident was planned by Sadaijin, Fujiwara no Tokihira[藤原時平（ふじわらのときひら）] for whom Michizane was a nuisance.
In 903, he died with disappointment in Dazaifu. After his death, ominous incidents occurred in Kyoto and people thought these were caused by the ghost of Michizane. Because of that, his honor was recovered and he was enshrined in Tenmangū[天満宮（てんまんぐう）] Shrines as a god, Tenmandaijizai-tenjin[天満大自在天神（てんまんだいじざいてんじん）] to console his soul.