NEW YORK, May 21-Steel industry executives complained here today that President Reagan's eight-month-old program to cut steel imports has taken hold slowly, with foreign steel continuing to flood into this country.

But they refused to write off the presidential initiative of last September, giving it at least a 50-50 chance of reducing imports in the long run.

"The problem is not on the part of our government, but on the part of foreign governments" that have "shipped excess tonnage in to beat the system," Dominic B. King, general counsel of U.S. Steel Corp., said at a press briefing in advance of the annual meeting of the American Iron and Steel Institute (AISI).

"We are now suffering from the excesses of other nations, not the failure of our government," continued King. He said foreign steel suppliers would have to make drastic cuts in their American sales in the last half of the year to comply with the president's target of reducing finished steel imports to 18.5 percent of U.S consumption.

However, projections by Data Resources Inc. (DRI) of Cambridge, Mass., show steel imports this year will total 23.2 percent of U.S. consumption, said Bethlehem Steel Corp. Senior Vice President Curtis H. Barnette. This is higher than the Reagan administration target but still lower than the record 26.6 percent import penetration of 1984.

According to DRI's estimates, import penetration will decline from the first quarter's 27.3 percent, which was higher than last year's average but lower than the 1984 fourth-quarter surge. Second-quarter imports are expected to amount to 23.1 percent of the domestic market, while the level for the third and fourth quarters is expected to be 21.3 percent and 21.4 percent, respectively. Looking ahead, DRI predicts 1986 and 1987 imports will stay at about 21 percent.

There was a note of gloom during much of the press briefing, including a reminder that the industry recorded its third straight year of losses in 1984.

The most positive sign was that the 1984 loss of $290 million was less than the $3.6 billion in red ink spilled in 1983 and the $3.2 billion 1982 loss. "The important point is that there was no recovery in 1984 from the financial devastation of the prior two years," said Paul R. Roedel, head of Carpenter Technology Corp.

Employment continued dropping last year, and the AISI reported that January's total of 150,500 workers was the lowest figure recorded for the industry since June 1933, when it first began compiling figures. The work force is less than one-fourth of peak industry employment of 544,300 in 1953.

Along with employment, steel industry wages -- once among the highest of any manufacturing workers in the world-are dropping along with the industry's capacity to produce steel.

These decreases are part of the painful process of restructuring the industry to meet the world competition of the 1980s, in which more nations -- especially the newly industrialized countries of the Third World -- have joined the global steel trade.

This wrenching process is making American steel makers more competitive, steel executives asserted, although they continued to blame "unfairly traded" foreign steel for much of the industry's troubles.

R. W. Maier, president of LTV Steel Flat Rolled and Bar Co., said U.S. steel makers increased their productivity 26 percent from 1981 to 1984. Last year, he said, the number of worker hours it took to make a ton of steel in the United States dropped from 8.1 to 6 -- a better record than Japan, West Germany, Great Britain or France.

"The U.S. industry, in terms of productivity measurements, is competitive on a global level," said Maier. "We are not at world-class quality yet," said Robert D. McBride, president of National Steel Corp. Half of his company has been bought by Nippon Kokan K.K. (NKK), a giant Japanese steel maker.

"We have a way to go to compete with the Japanese. But we're well on our way," McBride continued.

But he complained the industry has trouble raising the money it needs to modernize. "We have a capital problem because we have a profitability problem. It's a Catch-22 situation. Without capital we're not going to get the profitability."

A trio of executives -- Roedel; W. Bruce Thomas, chief financial officer of U.S. Steel, and Donald W. McCambridge, manager of legislative analysis and tax planning for Bethlehem Steel -- said the Reagan administration's new tax proposals are likely to hurt industry efforts to modernize by removing investment incentives.