New figures from the Investment Association show the industry saw net outflows of £399m from UK authorised investment funds last month.
Laith Khalaf, a senior analyst at Hargreaves Lansdown, said the figures came as a "surprise".
He added: "One possible reason behind the poor numbers is repatriation of funds by international investors ahead of the Brexit vote, which could explain the exceptional levels of outflows seen in the last two months."
Read more: Equity funds out-class other investments
The Investment Association reported that the targeted absolute return sector was the most popular during February, with £243m of net retail sales. This was the first month since October 2015 that the sector had been the highest ranked.
Funds under management were £855bn - up from £843bn in January, but down from £874bn in February 2015.
"Caution was still evident amongst retail investors in February as they reduced their holdings in investment funds amid volatile markets,” said Guy Sears, interim chief executive of the Investment Association, the investment managers trade body.
"Outflows were seen across a range of asset classes, but we did see investor appetite for absolute return and equity income products."
The UK equity income sector was the second most popular sector last month, with net retail sales of £214m.
Commenting on the figures, Khalaf said the popularity of UK equity income funds demonstrated "continued appetite for income-producing funds in a low interest rate environment".
He added: "The exodus from investment funds continued into February as investors took more money off the table. Funds invested in UK shares and UK commercial property took a hit, as did strategic bond funds.
"This comes as a surprise seeing as there was a big bounce in stock prices in mid-February, as some measure of confidence returned to the market."