Wolfowitz spoke a week before the opening in Hong Kong of the World Trade Organisation meeting, which will take up the thorny agricultural protectionism issue.
Wolfowitz told a National Foreign Trade Council dinner in New York that farm trade barriers were simply "harmful and indefensible".
"There is so much at stake for poor countries," Wolfowitz said on Friday. "The potential gains are huge."
"Reducing trade barriers is the key to reducing poverty," he added.
The World Trade Organisation is to hold a ministerial conference in Hong Kong on 13-18 December in a bid to breathe new life into the Doha Round of trade negotiations, which have foundered largely on the issue of farm subsidies in rich countries.
British Finance Minister Gordon Brown called on Friday for the abolition of all European Union farm subsidies and the alignment of agricultural customs duties with other EU economic sectors.
"There is so much at stake for poor countries. The potential gains are huge"
World Bank President
His plan to reform the EU's Common Agricultural Policy (CAP), which would take effect between 2015 and 2020, was unveiled in London ahead of a meeting of the Group of Seven finance ministers, whose principal goal is to spur momentum in deadlocked global trade talks.
The EU is currently locked in fierce bargaining on its budget, with Britain leading a campaign against lavish spending on farm subsidies in the face of a flat refusal from France to see any changes.