Senate Majority Leader Robert J. Dole (R-Kan.) warned Japan in blunt, tough terms today that it faces stiff protectionist action from an angry Congress this year unless it moves quickly to ease its burgeoning trade surplus with the United States.

Dole, here on a tour of Asian nations with six other senators, said bills aimed at punishing Japan for perceived unfair trade practices have gathered so much support that Congress is likely to override a presidential veto.

"The plain fact is that I have never seen stronger congressional sentiment for action on the trade front," Dole told Japan's National Press Club in a luncheon speech.

"My colleagues, even the most responsible ones, are tired of what they perceive as basic unfairness. They are convinced of the need to address the situation one way or another, and to do it quickly."

Dole's group is one of several congressional delegations to pass through here this month making the same point to Japan, whose $36 billion trade surplus with the United States in 1984 is expected to grow to $50 billion this year.

The majority leader's assessment of the mood of Congress was backed by others on the trip. Sen. Daniel Patrick Moynihan of New York, the only Democrat in the delegation, said Congress is being pushed to action by the Reagan administration's refusal to tackle the record U.S. trade deficits, which soared to $123 billion in 1984 and could top $150 billion this year.

Moynihan said any trade bills passed by Congress would be directed at "getting the administration's attention" as well as Japan's.

Dole, in his speech, said last month's "action program" by Prime Minister Yasuhiro Nakasone to open Japan's markets to foreign goods "ignored the urgency of the problem" by spacing import-liberalization steps over three years and by failing to respond to many U.S. priorities.

In a meeting later today with Keijiro Murata, minister of international trade and industry, Sen. Daniel J. Evans (R-Wash.) called Nakasone's effort "too late, too little, too slow."

Dole, though, denied that his group was talking tough. "We left the tough guys in Washington," he said in answer to a question.

Japanese officials appeared somewhat dazed from the series of attacks by visiting congressmen and Clayton Yeutter, the new U.S. trade representative. In interviews here today and in questions to Dole, they seemed unsure of how to forestall congressional action.

They pointed out that nothing Japan could do now would have an immediate impact on its trade surplus with the United States.

Moreover, the Reagan administration estimated that even if Japan lifted all import barriers, sales of U.S. products would increase by no more than $10 billion to $12 billion, which would barely make a dent in the Japanese trade surplus.

Dole, nonetheless, insisted "the fundamental problem is that your market is not sufficiently open to our products and services. Its opening is an essential first step toward solving our trade problem."

He said Japan's markets are closed to U.S. products, such as telecommunications equipment and other high technology goods, "when they are the best in the world." Dole also listed lumber, plywood and paper as products kept out of Japan by high tariffs, as well as farm goods whose sales are restricted by quotas.

"American producers face a multitude of market restrictions here. You impose quotas on beef, citrus and other agriculture products despite limited domestic production and high potential demand. You have prohibitively high tariffs on wine, chocolates and wood products," Dole continued.

He cited Japanese restrictions on imports ranging from tobacco to satellites, and said the country's system for testing and certification "is notorious among foreign businessmen. It has accomplished in many areas what tariffs and quotas could not do."

Dole, like Yeutter, urged Japanese businesses to increase their purchases of U.S. manufactured goods, a move many of them seem prepared to make.

But the bulk of his message was that trade has become a major political issue, and that congressmen facing reelection will press legislation against Japan and other nations that are seen as using unfair trade practices against the United States.

"In this highly charged atmosphere," Dole said, "administration opposition would not be enough to forestall action for long, and even a presidential veto might be swept aside." As a result of the growing trade deficits, he said, Congress is becoming increasingly skeptical about launching a new round of global trade talks, a prime goal of the Reagan administration and the Nakasone government.

"There is very little we could give up in new negotiations, and to expect others to make significant unilateral concessions seems totally unrealistic," said Dole, echoing views of Democratic colleagues such as Sen. Lloyd M. Bentsen (D-Tex.)