The announcement follows close to six months of speculation about negotiations between the two companies.
While AWB had made no secret of plans to offload its Geneva business, it had previously confirmed only that it was in talks with an international commodities company.
AWB managing director Gordon Davis said the price would be disclosed once the final deal was signed.
Gavilon president and chief executive Greg Heckman said the proposed joint venture provided an opportunity for the company to expand its global footprint in a meaningful way with a well-established Australian agribusiness.
Known best to growers in its previous incarnation as ConAgra, Gavilon operates the fifth largest grain merchandising operation in the United States and the country’s second largest fertiliser distribution network.