Pimco, a unit of Allianz which manages around $1.47 trillion (£978.9 billion) in assets, said the board will help guide its investment process.
“Sharing insights on how global macroeconomic and geopolitical policy affects markets and investments is an important part of the value we bring to investors as stewards of their assets, so our clients will benefit greatly from the experience and insight the Global Advisory Board will provide to us,” its chief executive Douglas Hodge said.
Brown's spokesman told the BBC that the former Labour MP would not financially benefit from the appointment.
"Any money goes to the office of Gordon and Sarah Brown to support their charitable and public service work," the spokesman said.
