Two Chinese restaurant chains are locked in a battle that may prove as hot and spicy as the Hunan food they sell.

The owner of Mr. K's at 21st and K streets NW and the House of Hunan -- one on 19th and K streets NW and another in Vienna, Va. -- is suing the owner of Hunan at Pavilion in the Old Post Office on Pennsylvania Avenue NW; Hunan Express -- in downtown eateries Connecticut Connection and National Place -- and Hunan restaurant in Rockville.

In a lawsuit filed recently in U.S. District Court, John Kao, president and majority shareholder of Mr. K's, charges that Steven N. Yung, owner of the other chain, "deliberately deceived the public" by using the same oxblood coloring, lettering and Chinese symbols as Mr. K's uses on its signs, advertisements, menus, napkins and tablecloths. The suit asks a judge to bar Yung from using the same symbols, on the grounds that their continued use by the restaurants owned by Yung "will cause confusion and weaken and erode the value" of Kao's business.

Already, the lawsuit noted, "many area restaurant critics have been confused . . . and have been led to believe, incorrectly, that the 'Hunan' is owned and operated by the same management which owns Kao's restaurants."

Yung, through his lawyer, denied any wrongdoing and said he would vigorously oppose the lawsuit. Yung used to be manager of the House of Hunan at 19th and K streets NW, the suit said. "He was instrumental in building the House of Hunan," said Yung's lawyer, Morris Kletzkin. Yung left voluntarily in December 1982. However, he still retains about 22.5 percent of the stock in the restaurant.

Kao let the matter rest until now, "because there is a great reluctance within the Chinese community to bring suit against someone else in the Chinese community," said Kao's lawyer, J. Carter McKaig. "But the situation simply became intolerable," he added.

The last straw appeared to be the planned opening of a new restaurant by Yung at 20th and K -- about 150 yards away from Mr. K's. The new restaurant, to be called China Rose, is slated to open this spring, the lawsuit said.

Yung "intends to place a pair of four-ton hand-carved white marble lions in front of the 'China Rose' restaurant. . . . These lions are identical in every respect to the marble lions in use at . . . Mr. K's restaurant," the lawsuit charged. It added that Yung has employed Mr. K's same interior designer and architect, and that "the layout, design, furnishings and interior decor of the China Rose is or will be substantially the same . . . as Mr. K's."