Tourism minister Barbara Follett will stand down at the next election following the scandal over expenses.
Follett said she was stepping down to spend more time with her children and grandchildren.
In May, the Daily Telegraph revealed that Follett claimed £25,000 over four years for security patrols outside her second home in Soho, London. She has since said she will pay back £32,976 for the security services and other expenses.
Follett took over from Margaret Hodge in October 2008, and has been Labour MP for Stevenage since 1997.