The Hot Shoppe on Wisconsin Avenue near Van Ness Street NW - one of the last of a slowly vanishing chain of family-style restaurants - will close Friday and is soon to be replaced by a more elaborate dining spot.

The Marriott Corp., which has operated Hot Shoppes here for 50 years, plans to convert the 38-year-old Hot Shoppe at 4110 Wisconsin Ave. NW either to a Joshua Tree or to a Franklin Stove restaurant, serving more expensive roast beef, steak and other dinners. Marriott now has a Joshua Tree in McLean and a Franklin Stove in Fairfax City.

Thomas E. Burke, Marriott vice president for corporate affairs, said yesterday that the new restaurant will open by the end of the year. He attributed the Hot Shoppe's closing to economic factors. "The volume on this one has been gradually slipping over the years," Burke said. A market study, he added, showed that a dining place such as Joshua Tree would be more profitable.

In recent years, Marriott has closed most of its Hot Shoppes because of rising costs and declining profits.

The Hot Shoppes have had higher food costs than fast-food outlets, officials say, because they have more varied menus. Their labor and overhead costs are comparatively higher, officials note, partly because Hot Shoppes stay open more hours a day than fast-food and dinner-only restaurants. Corporate officials have also described the Hot Shoppe's return on Marriott's investment as inadequate.

After Friday's closing, officials, said, only eight Hot Shoppes will remain, including six in the metropolitan Washington area. There once were 40 Hot Shoppes.

The Hot Shoppe at Wisconsin Avenue and Van Ness Street is next to one of Marriott's Roy Rogers fast-food restautrants. Burke said the Roy Rogers will remain open.

Over the years, the Hot Shoppe has drawn teenagers from nearby high school, neighborhood families and tourists. Among its frequent customers has been J. Willard Marriott, the corporation's chairman and founder. "The chairman used to go to this one regularly," Burke said.