Andrej Holm, in charge of housing in the state of Berlin, showed "by his statements and in interviews" about his past that "he was unable to look clearly at himself and to draw the consequences," the head of the regional government, Michael Mueller, said in a statement.
The mayor added that "especially in Berlin, which was the epitome of a divided city, there must be no doubt about the work to overcome the past" -- a reference to confronting the painful legacy of authoritarian rule.
The 45-year-old Holm's ties to the Stasi were revealed by a local Berlin newspaper last month just as he was taking over the housing position.
The son of a Stasi officer, he volunteered to join the agency at the age of 14 and four years later enrolled in its school as an officer cadet. He worked for the Stasi in the period immediately before the fall of the Berlin Wall in 1989.
Holm is close to a far-left party, die Linke, that evolved from the once-ruling East German communist party, and in the last decade was active in local radicalism, notably among Berlin's squatter movement.
He became a senior official with the rank of secretary of state in Berlin, which has the status of a city-state in Germany's federal structure.
He admitted his Stasi past and expressed his apologies over the past weeks, but was unable to tamp down the controversy.
Since German reunification in 1990, there has been a long list of political figures and officials forced to resign over their ties to the Stasi, whose network of spies, informers and prisons underpinned Communist rule for four
It was also revealed that Holm, a sociologist specialising in urban gentrification, did not reveal the full extent of his Stasi involvement when he was hired as a teacher at Berlin's Humboldt University in 2005. An inquiry
has been opened into this matter.