If you haven't heard already, China's most influential leader Deng Xiaoping narrowly escaped assassination recently when an enraged general, passed over for chief of staff, fired a pistol at the vice premier.

Or perhaps you were unaware that many Chinese have organized a movement to restore the alliance with the Soviet Union.

These are some of the alarming tales that have swept the Chinese capital this spring. The mix of rumor, black information and conjecture have sometimes obscured the air almost as much as the dust storms that blot out much of the skyline. Puzzled diplomats and Chinese, who have had rather good luck in the past year with carefully planted rumors coming true, wonder where this wild stuff is coming from.

Many stories, such as Deng's near assassination and the Sino-Soviet alliance, can be tracked back to Perking's most mischievous adversaries, Taiwan and the Soviet Union. But that does not alleviate the unease felt by Chinese who hear the reports, for they are accustomed to small kernels of truth in the underground stories they hear.

"Do you think there is something to it?" said on sophisticated Chinese official, genuine concern on his face, where the report of the Deng confrontation reached him via wire service reports from Taiwan. Chinese governments formely ignored such reports, as meaningless enemy propaganda, but this government needs foreign help and foreign confidence, and its official Foreign Ministry spokesman this time forthrightly labeled the assassination report "sheer nonsense."

The Taiwan story was the latest triumph a Taiwan group of analysts who watch mainland affairs and pick up mainland gossip, attach new facts to it and occasionally offer it to Western news agencies. This report in Taiwan's English language China News exploited the recent absence from public view of Politburo member Xu Shiyou, a tough old general recently transferred from his post as Canton military region commander.

The story said Xu angrily accused Deng, an old ally, of ungratefulness for making him chief of staff. When Deng retorted with a characteristic flippant remark, Xu pulled out a gun and fired. The shot hit a Deng bodyguard who, according to the story, fired back and seriously wounded, Xu.

This report, front-page news in Hong Kong's leading English language newspaper, the South China Morning Post, was accompanied by the appearance of the "League for China's Renewal," a mysterious group with a list of addresses for foreign correspondents in Peking. The group mailed pamphlets in Peking denouncing "American imperialism" and calling for immediate Sino-Soviet rapprochement.

"Only through the normalization of Sino-Soviet relations can world peace be assured," the pamphlet said. "This is the most urgent task facing China." bIt finished off with an attack on Deng, calling him a traitor to "the interests of the Chineses people" by aligning himself with the Americans.

The source of the pamphlets was less clear than the assassination report, but the language and approach seemed so close to that of a Soviet radio station recently attempting to pose as the voice of Chinese dissidents that most Peking observers blamed Moscow.

With nerves frayed, however, China's information chiefs took the unusual step of publicly denying, in special front-page Hong Kong advertisements, reports of a speech by Politburo member Chen Yun that had appeared in friendly Hong Kong publications. In the alleged secret speech, Chen vaguely suggested it might be time for direct criticism of Mao Tsetung, the late Communist Party chairman who remains officially revered here despite the political tumult he caused in his last years. The official New China News Agency called the speech text "a complete fabrication" in the advertisements.

This week, the rumor storm seemed to have abated a bit, and the mysterious Gen. Xu appeared, apparently healthy, at a May Day celebration in Nanjing. A sense of humor had returned to the Chinese Foregin Ministry. When a playful American diplomat asked a Foreign Ministry spokesman at a party just what Xu was doing in Nanjing, not his usual place of assignment, the Chinese official responded with a grin. "He's recovering from his wounds," he said.