Euan Munro is set to leave Aviva Investors after seven years at its helm, with a replacement chief executive expected to take up the role with immediate effect.
The top spot at Aviva Investors will be filled by Mark Versey, the chief investments officer of real assets at the fund house.
Mr Munro, who first joined the company in 2013 and has served on the Investment Association's board since 2017, is to pursue a career outside of Aviva.
His successor Mr Versey joined Aviva Investors in 2014 and most recently led its £47bn real assets business which includes infrastructure, real estate and private debt markets.
He also sits on the investment committee of the Investment Association and chairs its sustainability and responsible investment committee.
Aviva said the appointment was "another important step" in the delivery of its new strategy, which includes doubling down on its UK, Irish and Canadian markets and pulling back from international operations.
Amanda Blanc, chief executive at Aviva, said its fund house had a "significant role" to play in the delivery of the wider company's strategy, including providing Aviva customers with "attractive investment solutions for each step of their lives".
She added: "Aviva Investors is a core part of Aviva and its investment capabilities are critical to our ambition to be the UK’s leading insurer.
"I have been impressed with Mark’s determination to strengthen Aviva Investors, deliver excellent investment performance and extend our leadership in responsible investing."
Mr Versey said Aviva Investors had a "significant opportunity" to grow the business organically and help Aviva meet its ambitions in the UK.
He added: "The business has strong capabilities in fixed income, credit, equities, multi-asset and real assets, as well as being a leader in responsible investment.
"My overriding priority will be to provide our customers with strong and consistent investment performance to deliver the outcomes they are looking for, including meeting net zero emission targets through sustainable investments."