The Reagan administration's new restrictions on U.S. computer exports to South Africa, which will be published Monday, has drawn criticism from members of Congress who view them as too weak.

The Commerce Department's new rules prohibit the export of U.S. computers, software and related technology to South African agencies that enforce that country's system of racial segregation, called apartheid.

Rep. Howard Berman (D-Calif.) said the rules are "somewhere between worthless and satisfactory," and that Congress would consider legislating tougher restrictions after its winter break.

The rules implement part of President Reagan's executive order of Sept. 9, when he announced limited economic sanctions against the Pretoria government. That order included a ban on new loans to the South African government, and led to a ban on the importation of South African gold coins, called krugerrands.

Reagan's order followed House passage of a bill that would have imposed stricter sanctions on the Pretoria government, and caused the Senate to postpone indefinitely its vote on the bill.

The computer export rules prohibit the export of "all U.S. computers, computer software, or goods or technology to service computers to all apartheid enforcing entities of the South African government."

These entities include the South African military and police, as well as a list of government agencies, including the ministries of justice, law and order, home affairs and national education, and manpower. The entities also include unspecified "other agencies" such as "local, regional and 'homeland' agencies."

The State Department said in the document that "apartheid enforcing agencies" does not include the ministries of finance, communication and public works, mineral and energy affairs, or agricultural economics and water affairs.

Berman said the list of agencies is narrower than that favored by Congress.

A Quaker group, the American Friends Service Committee, charged that the list omits several South African agencies involved in administering apartheid, including the Department of the Prime Minister and the Ministry of Communications and Public Works, which builds prisons.

One provision that has drawn mixed congressional reaction allows the Commerce Department to grant exemptions for exports promised in contracts signed before the president's order. The congressional plan would not have allowed such an exemption.

The provision "seriously weakens the ban on computer sales and is not consistent with the provisions of the Executive Order or the intent of Congress," six senators said in a Nov. 8 letter to Commerce Secretary Malcolm Baldrige. Six representatives sent a similar letter.

Baldrige replied that requests for exemptions would be considered on a case-by-case basis, and would be "considered only if the export does not involve the police or military, would not be used to enforce apartheid, and would not otherwise contravene the purposes of the Executive Order."