Sky News understands that Russell Hamblin-Boone, who joined the Consumer Finance Association (CFA) as its chief executive in 2012, is to leave in the coming months.
His departure will be announced later this week, according to City sources.
Mr Hamblin-Boone, who is expected to hand over responsibility to an executive drawn from within the CFA ranks, will depart after a period in which his members became some of the most vilified participants in the UK financial services sector.
The body's members include some of the most recognisable names in the short-term credit industry, such as The Money Shop, Payday UK and QuickQuid.
Wonga, which for several years was the biggest player in the market, is not currently listed as a CFA member.
The sector has seen the number of companies providing so-called payday loans shrink substantially since the Financial Conduct Authority introduced a cap on the cost of borrowing.
The CFA is headed by Caroline Walton, who runs the corporate affairs function at Dollar Financial UK.
Dollar's operations - which in the UK include the Money Shop brand - are in the process of being broken up and sold off by its controlling shareholder.
It was unclear on Tuesday when Mr Hamblin-Boone, who previously worked for the Energy Retail Association and the British Retail Consortium, would step down.
The CFA declined to comment ahead of an announcement about the change of leadership.