The Reagan administration plans to issue orders to the Environmental Protection Agency and other Executive Branch agencies to bring government regulators in line with President Reagan's plans to ease the impact of regulation on businesses and individuals, a top administration official said yesterday.

"We're going to be putting down very hard rules for them," said James C. Miller III, the new director of the Cabinet-level task force on deregulation headed by Vice President Bush. The result will be a "significant change in the way agencies issue regulations," Miller predicted.

The EPA and the Occupational Safety and Health Administration are the two initial targets of the deregulation campaign because of the impact of their regulations on business, he said. They will be under instructions to issue regulations only when necessary, and to make certain that their regulations impose the minimum costs on society, he added in remarks to a meeting of the National Retired Teachers Association and the American Association of Retired Persons.

Reagan aides have outlined three major moves in the deregulation campaign. The first was the 60-day freeze on new, "nonessential" regulations ordered by Reagan last week.

Now administration officials are drafting a presidential executive order to replace the regulatory order No. 12044 issued by President Carter, which expires in April. Carter's order instructed bureaucrats to consider the costs and benefits of new regulations, but did not impose this as a strict requirement. According to administration officials, the new order will set down Reagan's overall instructions to federal regulators requiring them to adopt the least costly method of achieving regulatory goals.

The point of the order will be to put White House authority firmly behind the deregulatory philosophy of Reagan and his key aides, including Miller; David A. Stockman, the director of the Office of Management and Budget; And Murray Weidenbaum, chairman of Reagan's Council of Economic Advisers.

Stockman, Weidenbaum and Miller are on record in a tall stack of speeches, articles and books over the past six years as favoring wholesale changes in federal regulatory methods.

Their views are expected to dominate the new administration's deregulation strategy.

The third part of the deregulation strategy involves the new Paperwork Reduction Act passed last year which authorized the OMB to regulate the forms issued by federal agencies to companies and individuals and the records that must be kept to comply with federal regulations. Because virtually all federal regulatory programs require forms, this gives the OMB a powerful handle over regulation, one administration official said.