Three new bars featuring nude and nearly nude dancers have invaded Connecticut Avenue, adding a touch of Washington's 14th Street gaudy strip life to the affluent and more subdued Dupont Circle neighborhood.

Long a key to the commercial and residential renaissance of the city's center, Dupont Circle has been a refuge for artists, hippies, homosexuals and political radicals as well as home for conventional and well-heeled businessmen and bureaucrats.

And now the strip joints are coming. The Old Stein, a traditional German family restaurant for 30 years at 1339 Connecticut Ave., suddenly changed its exterior and interior last month and opened as The Cat's Meow II with both male and female dancers and a new clientele.

Sabina's Harem, late of 14th and K streets NW, already had moved to the second floor above the Old Stein in December. Sabina's offers go-go dancers at lunch and a burlesque show in the evening and a hustling doorman outside.

Three doors away, the Foxfire opened Sept. 17, replacing a defunct gay bar. It features continuous entertainment of close-to-nude women dancing on a large mirrored stage.

These clubs join four other long-established strip bars in the Dupont Circle neighborhood, but most of them are tucked away on side streets. The new ones are all out front, on Connecticut Avenue.

The Dupont Circle strip joints now outnumber the better-known but seedier and raunchier bars that line 14th Street between H Street and New York Avenue NW. The 14th Street strip, once the center of traditional nightclubs and burlesque shows, became known in recent years for its garish lights, loud music and unabashed anatomical displays by female dancers.

Community reaction to the topless-bottomless bars runs from outrage to studied indifference in a neighborhood known for its diverse life styles. Merchants and residents interviewed say their greatest concern is that if more clubs move to Dupont Circle, Connecticut Avenue may replace the 14th Street strip, which has already lost six clubs to new office building development.

Robert Zanville, 72, who opened the Old Stein in 1951, is sure he has made the right decision in transforming his family-owned restaurant into a go-go bar. And his son Al, 46, also a partner, is equally sure that naked dancers won't hurt Connecticut Avenue.

"It the bar is positively going to go," the elder Zanville said as he sat in the crowded front room where Brandy, a slender, dark-haired dancer, was rapidly removing her scanty lingerie to the beat of a disco record. "It will be bigger than the Playboy Club. You wait."

Al Zanville, a big man with a big smile, greets customers at the door and collects a three-dollar cover charge from the women arriving to see the male dancers who perform in the back room. There is no cover for the men watching female dancers in the front room. "We're property owners," he said between customers. "We're not going to hurt the neighborhood. It's not like we're bringing in smut from L.A. We're established and we're staying," he said.

Sabina Stiles, who has hired many of the burlesque stars of the defunct Silver Slipper nightclub and advertises "nude dancing girls" at her front door, says she hopes Connecticut Avenue retains its "class" and does not become another 14th Street.

Also hopeful of staying put are Bob Bobyak and Carol Mace, who opened the simply decorated Foxfire after years of working on 14th Street. The Foxfire, unlike its 14th Street counterparts, has no garish lights, explicit photographs or loud music. Nude dancing is not mentioned on any of its low-key signs.

"This place will never be like 14th Street," says Bobyak, 30, who is his own bartender. "First of all, there is no room for anyone else to open here, and second, we run a clean business."

Next door, Fred Tork, manager of Imperial Valet, is indifferent to the new bars. "I don't care if they are here. They have no effect on my business."

But Jackie Eagan, co-owner of Mr. Eagan's Bar next to The Cat's Meow II, is unhappy. "We're getting prostitutes, pimps and dope," she said. "We run a nice place here. A lot of our gals are single. I'm not going to have my female customers harassed on the street. I won't stand for it."

Up the street, Beni Isfahanny, manager of Pasagad Carpets of Isfahan at 1351 Connecticut Ave., is concerned about changes in the appearance of the block. "It's bad for the neighborhood. They are incompatible with our business," he said. "We will do our best to stop them."

But Denton Williams, executive vice president of the oldest business on the block, the Randall H. Hager real estate firm founded in 1904, probably reflects better the accommodating attitude of the Dupont Circle community. "They are a different style of business for this block. But it is a free country," Williams said. "We've been here a long time, and we'll be here when they are gone."

The Dupont Circle Citizens Association, a 60-year-old organization that has fought to protect the historic and low-scale character of the neighborhood, has yet to take a position on the strip joints, according to first vice president John R. Immer.

But James Oliver, chairman of the Dupont Circle Advisory Neighborhood Commission, says the commission "does not look with favor on those establishments. We have asked the city to enforce the zoning law which deals with sexually oriented businesses. It is our strong feeling that Sabina's, the Cat's Meow and the other one the Foxfire do fall under the zoning code and ought not to be there."

The restrictions on sexually oriented businesses were added to the zoning regulations in 1977 to limit establishment of new bars, theaters, bookstores and other businesses that emphasize "specified sexual activities and specified anatomical areas."

Few persons have applied to open a business under the new category, and most have opened instead as ordinary bars or clubs. Says city zoning administrator James Fahey, "Basically, they gamble. They just open up. They give it a try."

Meanwhile, the new bars appear to be doing well.

Roxanne and Tinker, dancers at the Foxfire, say they are glad to be working at a club away from 14th Street.

"The business is selling champagne and sexual favors on 14th Street," said 19-year-old Roxanne. "But not here." Both women say all they are required to do is come to work on time and dance. "That's why I like it here," says Roxanne.

"Go-go is prostitution on 14th Street," says Tinker, a 25-year old veteran of the strip. "Those guys have been making out like bandits for years on 14th Street. I hope this place makes it because I don't want to go back to 14th Street. That place is hell."

Foxfire owner Bobyak thinks he has found the perfect location for his bar. "This is the place I wanted," he said. "It is nice here. You don't get hit up the side of the head here . . . . After 12 years on 14th Street, this is heaven."