The research carried out by MetLife showed 11% of the 1,066 retirees were unhappy with drawdown as their retirement income choice.
More than one in five of the customers surveyed overall (21%) admitted they failed to understand the risks when they invested.
Another 12% regretted not taking advice before investing in drawdown.
Since the reforms around 90,700 savers have been investing in drawdown plans compared with just 6,700 in the first three months of 2014, according to ABI stats.
MetLife warned that these drawdown regrets could be putting new pension freedoms at risk.
The biggest fear for new drawdown investors was the risk of volatility - nearly half (49%) were worried about future investment market volatility while 51% were banking on growth to boost their funds.
Nearly half of advisers asked by Metlife (48%) reported a rise in the number of drawdown clients suffering cuts to income and capital while, on average, advisers across the country said 25% of clients have suffered drawdown losses.
MetLife is supporting a drive to ensure savers understand all the choices available to them and has launched its Real Pension Freedom campaign, supported by advisers and focusing on the valuable role guarantees can play in retirement.
Simon Massey, wealth management director at MetLife UK, said: “The fact that so many drawdown customers are unhappy and did not understand the risks to their cash in drawdown is a real threat to the success of pension freedoms.
“Savers are not being offered the retirement income solutions they need because of a lack of innovation in the market and in many cases they are not receiving essential expert advice on retirement planning.
“Guaranteed solutions have a valuable role to play in delivering real pension freedom and should be part of all retirement planning conversations to avoid potential problems in the future for people choosing conventional drawdown without understanding the risks.”