The 35-page guide, aimed at governments, development banks, aid agencies and export credit agencies, emphasises the financial risks associated with large-scale dam projects.
The guide is a bold move for WWF, whose consensus-building approach has left it open to accusations of "greenwash" in the past.
This year, a £3 million pound partnership with a company that plans to develop a superquarry on an unspoiled Scottish island, drew accusations from other environmental organisations that WWF is too close to its corporate partners.
However, WWF defends its consensus approach. "We've never walked away from dialogue," said Doug Walker, communications manager at WWF Dams Initiative.
"There is a trend towards greater corporate social responsibility. But no one was speaking directly to investors."
Every year, between £19 billion and £29 billion is invested in dams, despite evidence they cause social and environmental problems.