Liu Zhijun, the longest serving railway minister, was found political and ethical misconducts, many of which are closely linked to Ding Shumiao, an executive of the Beijing Boyou Investment Management Corp, an inquiry report released by the Railways said.
Liu, 59, took advantage of his position to help Ding make huge illicit gains, state media reported.
The assets of Ding's company soared from 474 million yuan in 2008 to 4.5 billion yuan in 2010.
Liu was appointed vice minister of railways in 1996 and minister in 2003.
He was removed from his post and came under investigation in February 2011. He was expelled from the party in May.
Observers say the internal announcement signals that the investigation into Liu's misdeeds is drawing to an end.
