Matthaus-Maier, who was spokeswoman of the board of managing directors, was expected to see out her contract until the end of June 2009, but has been under pressure since her bank's involvement in string of bailouts of IKB Deutsche Industriebank.
The first of the four bailouts was enacted on July 30 2007, at which point KfW was at the head of a consortium of German banks supporting IKB. KfW is also a 45.5% shareholder in IKB, whose problems stem from the crisis in the short-term funding commercial paper markets.
"The turmoil surrounding the risk protection for IKB and continuing discussion of my person during the past months have created a situation in which I can no longer devote all my strength and health to my work, and this has been increasingly detrimental to KfW," said Matthaus-Maier in a statement released by the bank.
She has been temporarily replaced by fellow board member Wolfgang Kroh. The bank also announced last week that Christian Murach has been seconded from the board of KfW Ipex-Bank to the KfW Bankengruppe board under special assignment for an undefined period. KfW Ipex-Bank is the project and corporate finance arm of KfW.
Murach will be replaced on the KfW Ipex-Bank board by Christiane Laibach, who was a director in the aviation finance department of the bank.