Four Arab oil-producing countries have invested three to four times more in U.S. corporations, real estate and other assets than the Treasury Department admits, House investigators were told yesterday.

According to the Treasury, such combined governmental and private investment through 1980 totaled $51.3 billion. But David T. Mizrahi, editor and publisher of MidEast Report, a New York-based newsletter, testified that the total ranges from $150 billion to $200 billion.

Mizrahi said Saudi Arabia may account for $100 billion, Kuwait for almost $55 billion and the United Arab Emirates for $40 billion to $45 billion. He gave no figure for Qatar.

In 1975 the Treasury reached a unique understanding with Saudi Arabia to preserve secrecy about U.S. holdings by the Middle Eastern members of the Organization of Petroleum Exporting Countries (OPEC). The Treasury's technique is to group the OPEC countries under the heading "Other Asia."

In addition, Treasury asked the CIA to withhold nation-by-nation investment data from Congress. CIA compliance, the House Goverment Operations Committee said in a 1980 report, "appears to violate" an executive order requiring it to provide Congress with "national foreign intelligence information."

Mizrahi was unable to document his figures, telling Rep. Benjamin S. Rosenthal (D-N.Y.), chairman of Government Operations' subcommittee on commerce, consumer and monetary affairs, only that his data came from "Arab sources," including "one of the highest financial sources in the Persian Gulf."

That the Treasury is drastically understating reality was not disputed by subcommittee members and staff, for reasons such as:

* A Commerce Department admission that it knew neither the sources nor destinations of $60 billion that flowed into the United States in 1979 and 1980. "This is ridiculous," C. Fred Bergsten, Treasury's former assistant secretary for international affairs, said in a March 1980 memo. "Do we have any idea what is causing this? Can any new research help?" His successor, Marc E. Leland, is to testify today.

* A Securities Industries Association statement, filed with the subcommittee, cited "serious" shortcomings in Treasury's data-gathering and "not infrequent" clerical errors and non-reporting by firms supposed to list capital flows for the Treasury.

* Channeling of what Mizrahi termed "a good portion of the investments" through third parties, including foreign banks and companies established in the Cayman Islands, St. Vincent, other places in the Caribbean region, Luxembourg, Liechtenstein and Panama.

* A $5 billion gap between the Treasury's original $8 billion estimate of the true amount of Iranian assets and investments in this country and a subsequent estimate by a former Treasury official of $13 billion.

In other testimony, Christopher Story of London, editor and publisher of International Currency Review, said Saudi Arabia reimburses the Treasury for the salaries of about 30 employes despite a law that appears to require that they be paid "from appropriations." The Treasury did not respond to a request for comment.

Story said the Washington work of the U.S.-Saudi Joint Commission on Economic Cooperation, set up in 1974 by then secretary of state Henry A. Kissinger and Prince Fahd to help the Saudis invest their oil revenues, is done by the Treasury's Office of Saudi Arabia Affairs. In Riyadh, he said, the work is done by the office of the U.S. representative.

Under a 1975 agreement, Story continued, the two offices' expenses are met by a trust fund established by Saudi Arabia and held by Treasury. As of last May 31, the fund had paid out $434 million and had $168 million on deposit.

In a 74-page statement, Story estimated, on the basis of Department of Energy oil price projections, that Saudia Arabia's earnings from oil exports in 1981-1989 will total $1.69 trillion, compared with $369.9 billion between 1955 and 1980.

He also cited a secret 1978 CIA memo as a basis for asserting that, in the event of a financial crisis, the United States "stands ready to freeze" Saudi holdings.