Head of The Pensions Regulator (TPR) Lesley Titcomb is to step down from her post after she faced sharp criticism from MPs.
The organisation's chief executive will leave when her four-year contract is up in February 2019.
It follows a report being released a few weeks ago by two parliamentary committees which slammed the regulator for its "feeble response" to Carillion's underfunding of its pension scheme.
Influential MPs including chair of the Work and Pensions Committee Frank Field said TPR had been "chronically feeble" in not exercising its regulatory powers.
In a statement, Titcomb said it had been "a difficult personal decision" to leave.
"The end of my contract in February 2019 feels like the appropriate moment to find more time in my life for family, friends, other interests and opportunities," she explained.
Mark Boyle, chairman of the Board of TPR said he respected her decision to leave despite being "very sorry to lose her."
"She has been a real catalyst for change, working with energy and drive to get results and make a difference to the way we work," he said.
But Steve Webb, policy director of mutual insurer Royal London, slammed parliament for its harsh criticism of the TPR boss.
"The legitimate challenges about the work of the Pensions Regulator have recently crossed the line into unnecessarily and inappropriately personal vilification of the current CEO," he commented.
"This is particularly unfair given that many of the events in question happened before Lesley Titcomb was in post.
"If Parliament wants the best people to lead public bodies, it needs to reflect on whether those people will be willing to subject themselves to highly personal scrutiny and attack of the sort we have seen in recent months."