Chinese leader Hua Guofeng touched sensitive nerves on both sides of Europe's dividing line today by supporting German reunification and sharply attacking the Soviet Union.

In his remarks at a formal dinner marking the opening of his visit to West Germany, the Chinese leader hit a subject of special concern to the Soviet-led bloc of Eastern Europe by linking Peking to the idea of German reunification.

His West German hosts were ill at ease with his call on all "peace-loving" states to "demand a stop to aggression and hegemonism," a phrase Peking traditionally uses to describe what it regards as a Soviet policy of expansion.

In an unusually fast and sharp response to Hua's comments on reunification, the official Communit East German news agency tonight blasted Hua for supporting what it called "the revanchist designs of German imperialism against the German Democratic Republic," or East Germany, "a country that speaks for itself."

The East German commentary was titled "playing with fire, an apparent reference to Bonn's friendly but low-key welcome for the Chinese leader.

Hua's reference to hegemonism was undoubtedly not welcomed by his West German hosts, including Chancellor Helmut Schmidt, who were hoping that Hua would not use his visit here as a platform to attack the Soviets.

The West Germans have also gone out of their way to try to keep the Chinese leader from damaging West German-Soviet relations during his visit and Chancellor Schmidt, in his remarks tonight, made it clear Bonn was going to pursue its policy of detente with the Soviet bloc. It was a policy, he said, whose "record has been broadly positive" in terms of Bonn's treaties with East, which had made the region more secure.

Although Hua's three-week, four-country trip to Western Europe has been planned for some time, his arrival in Bonn comes at a time when Soviet leader Leonid Brezhnev has launched an all-out campaign to pressure the West, especially West Germany, not to go along with a proposed NATO plan to station new U.S.-built medium-range missiles on their soil.

Thus, Bonn is especially anxious these days not to allow any further irritants to enter the situation.

Earlier in the day, at the first private meeting between the Chinese Communist party chairman and Schmidt, the chancellor appeared to try and head off any anti-Soviet remarks by Hua by emphasizing Bonn's strong ties to the Western alliance, his conviction that a military balance of power was the essential ingredient of East-West detente, and by stressing the great importance of that detente to the West German people.

At tonight's state dinner, however, Hua said "our two countries, though geographically for apart and with different societies, do have a common task, namely to keep world peace and to fight aggression and war."

"We are convinced that it is absolutely possible to delay the outbreak of war and gain a longer peace when all peace-loving countries and people join together with effective means to demand a stop to aggression and hegemonism.

The 59-year-old Hua, who is also his country's premier, lavished praise on both Schmidt, who visited Peking in 1975, and on West Germany, which recognized Peking in 1972 and has since grown into China's third largest trading partner.

Twice today, both in the morning private meeting and tonight's dinner, Hua stressed Chinese support for the eventual reunification of Germany, now divided between the Western two-thirds of the former German reich and the one-third that is now Communist East Germany.

"It is abnormal," Hua said tonight, "that Germany has been artifically divided into two parts. The Chinese people understand fully how the German people feel in wishing to see their nation reunited and we support those legimate aspirations of the German people."

Chinese journalists here especially were calling attention to this portion of Hua's remarks, and Schmidt himself thanked the chairman for his understanding of the German people's wish to live under one roof some day," according to a spokeman for the chancellor.

Although Hua did not say what kind of a reunified Germany he saw, obviously one under Western domination would cause great anxiety to the Soviet Union and its other allies in the East. Indeed, the prospect of 80 million Germans reunited into a central European industrial superpower is an idea that still makes people, uneasy in many countries East and West.

Eventual reunification of the divided German nation has always been an official post-war position of West Germany and the Western allied powers. But in realistic terms, such a prospect cannot happen unless the existing East-West power blocs dissolve and a totally new international structure replaces it.

Nevertheless, talk of eventual reunification in some uncharted form has definitely been on the rise here and it has caused signals of irritation in East Germany, Poland and the Soviet Union.

Hua's emphasis on reunification today was believed to be more in the line of Chinese efforts to aggravate the Soviets rather than a strong commitment of solidarity for the Germans.

Even Chancellor Schmidt, however, has repeatedly raised the theme this year.

"I do not foresee under what auspices and conditions the Germans will get together again, but they will," Schmidt said in an interview with the Economist just last week.

Maybe only in the 21st century," he added. "I don't know. But it would obviously be wrong for any European nation to believe that the nation-state is normal for any nation but not for the Germans."