Former U.S. trade representative Robert Strauss expressed doubts yesterday that the Reagan administration's proposal to form a new trade department will improve America's trade position in the world.

"I'm not at all sure that consolidation is the answer" to the country's growing merchandise trade deficit, Strauss said of the administration's plan to merge the Office of the U.S. Trade Representative with trade and economic functions of the Commerce Department into a new Department of International Trade and Industries. The new department is designed to act as the country's single voice on trade policy.

"I'm neither knocking it nor praising it," Strauss said in a talk to the World Trade Forum. "I think the world will little note nor long remember it."

Strauss, former Democratic national chairman, served as President Carter's U.S. trade representative, which under present law is supposed to be the government's trade policy maker.

Strauss also predicted that the Reagan trade plan is unlikely to pass Congress, which is holding hearings on it.

Strauss suggested that, instead of implementing the planned reorganization, the White House give the present trade representative, William E. Brock, the same support that Strauss received from Carter.

"Everybody knew the trade representative spoke for trade" in the Carter administration, Strauss said. "Bill Brock has not been that blessed. He has no support in the White House. It all goes to Commerce. Everybody knows it, including him," Strauss asserted.

Strauss called Commerce Secretary Malcolm Baldrige, who fought in the White House for a trade department and is considered Brock's rival as trade policy maker, "a strong and able man." But he added that "there has not been that singleness of thrust" on trade issues that there was under Carter.