As the fighting has intensified between Vietnamese forces and Cambodian guerrillas, so apparently has the level of confrontation on the Chinese-Vietnamese border.

Both the Chinese and Vietnamese have issued reports recently that indicate that the border skirmishing and shelling between the two sides have been fierce. It is assumed here that the Chinese are attempting to increase the pressure on Vietnam to make the Vietnamese pay a price for their current offensive in Cambodia.

The Vietnamese have attacked first against noncommunist Cambodian guerrillas and then against the Khmer Rouge guerrillas, who receive heavy support from China. But in their official statements, the Chinese have said their attacks against the Vietnamese have been in retaliation for Vietnamese attacks across the border into China.

China's official New China News Agency said on Tuesday, for example, that the Chinese were retaliating for heavy Vietnamese shelling and assaults that had resulted in the killing, wounding or kidnaping of 26 civilians in two Chinese provinces during a week-long period.

The news agency said that the Vietnamese fired more than 5,000 shells and made six assaults on Chinese frontier guards, compelling the Chinese troops to retaliate. According to the New China News Agency, the Chinese in their response "wiped out some enemy outposts." Radio Hanoi, meanwhile, said that the Chinese had fired more than 1,000 shells at "many villages" located from four to six miles inside Vietnam. Vietnamese radio said the Chinese shelling "destroyed several villages and caused many losses in lives and property."

Analysts here say, however, that both sides appear to be exaggerating the level of military activity. Each side wants to portray the other as an aggressor. The Chinese have an added interest in showing Southeast Asian nations concerned about recently intensified Vietnamese attacks in Cambodia that China has the strength to retaliate against the Vietnamese.

But as a State Department official explained this week, "The level of rhetoric at times far exceeds the level of artillery shells."

Another State Department official said that both sides appear to have engaged in fairly heavy shelling, but that any attempt by the Chinese to invade Vietnam would prove "very difficult."

"If they were to try to do what they did in 1979, they would have to shift a lot more men to the border," the official said, noting that the Vietnamese had fortified the border region heavily during the past few years.

Analysts in Washington see no evidence so far that China's attacks on Vietnamese border forces exceed those that occurred in the spring of last year. Nor is there any evidence that China has built up its border forces to the degree that would be required to launch a major invasion of Vietnam.

For several weeks now, China has been making statements that would appear to be aimed at justifying attacks on Vietnam's border forces. On Jan. 10, a Chinese Foreign Ministry spokesman warned that Vietnam would "eat the bitter fruits" of its actions in Cambodia. On Jan. 29, the Chinese issued their most forceful statement to date. At the end of a visit to Singapore, Chinese Foreign Minister Wu Xueqian said at a press conference that China reserved the right to "teach Vietnam a second lesson" if it continued provoking the Chinese.

In early 1979, China attacked Vietnam in force on several major fronts, administering a "first lesson" to the Vietnamese that, in the end, looked more like a draw than a victory for Peking. The Vietnamese resisted more effectively than the Chinese apparently had expected them to, and their stiff response to the Chinese invasion brought to light a number of deficiencies in China's armed forces.

"It's a dilemma for the Chinese," said Harry Harding, a senior fellow at the Brookings Institution in Washington and the editor of a recent book on China's foreign relations. "The Chinese have few military options. They want to improve relations with the Russians."

"If the Chinese attack Vietnam, it will derail Sino-Soviet relations," said Harding. "But they want to demonstrate to the Soviets that their reconciliation with the Soviets is not unprincipled."

One Southeast Asian ambassador stationed in the United States argued that the Chinese are playing "a long-term game" in which Vietnam appears to be "the bad guy" on the international scene, suffers heavy losses in Cambodia and sees its economy deteriorate steadily.