Joan Mondale is the Vice President's wife, but the problem she faced is one many people in Washington have: how to make a furnished temporary house look like home.

Her answer is the one official wives learn: the paintings on the walls, the ashtrays and vases on the table make all the difference in the atmosphere of the house. Mondale had advantages most people in furnished houses don't have - years of studying and teaching are and practicing a craft, and the ability to borrow the art she likes best from her favorite museums.

The result is that the official Vice President's house, above the newly-painted white anchors on Observatory Hill, looks quite different from the way it did when Mrs. Nelson Rockefeller decorated it.

Gone are the three or four big American eagles fancied by Rockefeller, the safe, representational paintings, and the big controversial Rockefeller choice, the Max Ernest bed. Still aboard are the Kitinger Williamsburg classic traditional furniture and the several handsome Chinese and Korean pieces which belonged to Rockefeller's mother.

The 11 1/2-feet high white walls are a shade less yellow now, to show off better the paintings and the white and biege furniture. The assertive, brilliantly colored paintings, important sculptures and handsome craft objects make the house seem lighter, brigther and more spacious. The effect moves the 1891 towers-and-turrets Victorian house into the 1970s.

All that's left of former Vice President's taste in art is a Mussolini-modern eagle from Dwight Eisenhower's inaugural stand. Wrapped in plastic, the eagle still stands in the garden, waiting to be moved in favor of something more contemporary.

The art works are lent by 13 Mid-western museums and the Phillips Collection three chosen by Martin Friedman, director of the Walker Art Center in Minneapolis, an old friend and colleague of Mondale's. Most craft objects are from the National Collection of Fine Arts in Washington, chosen by the Smithsonian's Ralph Rinzler for a show several years ago, plus several pieces owned by the Mondales.

In place of the delicate flower painted china saucer are great pottery platters. "They'll hold lots of stubbed out cigarettes. We won't have to empty them as often," Mondale said.

Several of these pottery pieces were made by Mondale's own pottery teacher, Vally Possony. There are even one or two smaller pieces by Mondale herself.

Instead of stiff official bouquets, there are great bundles of forsythia and magnolia stuck in honeysuckle basket by Lucy George and Larry Youngbird of North Carolian.

In the dining room, the massive American empire table [WORDS ILLEGIBLE] marking it as once having [WORD ILLEGIBLE] in the Manhattan apartment of John Rockefellar Sr., a gift of his son, Nelson. Atop it are Jugtown potter Vernon Ray Owen's earthenware, and nearby is a pot by Otto and Gertude Naizler.

On top of the handsome Korean chest is a glazed black pot by Maria Martinez. In the living room, by the fireplace, is a garden set by Toshiko Takseru.

The Mondale children, Eleanor, 17, Teddy, 19, and William, 15, have their own favorites: the Class Oldenburg "Alphabet/Good Humor, 3-foot prototype," a piece as funny as the name; and James Rosenquist's "South from Horse Blinders" and "North from Horse Blinders suite - possibly because Eleanor, with two horses one of which she wants to sell - finds it easy to relate to.

Mondale said neither the children nor her husband has taken the "docent tour" she gave to the press at a luncheon yesterday, when she gave capsule catalog notes for several of the pictures.

The children also have had their effect on the house: Teddy's dirtbike road trophy sits on the marble side-board in the dining room. Eleanor and her art class at Georgetown Day School are working on a mural on canvas for the third-floor hall. For another kind of educated taste, the Mondales have dug a vegetable garden on the south hillside.

Upstairs, the Mondales have used some of their own pieces and some from the Navy (the house, originally the Admiral's House, still technically belongs to the Navy). "But our Danish modern teak is rather overwhelmed by this house," said Joan Mondale. "I've had to store most of our things.

Eleanor Mondale says the house doesn't have a ghost, so far they know. But Bess Abell, Mondale's aide, said the Mondales' dog, Bonnie, who is blind, spent some weeks bristling at things no one else could see. Joan Mondale said the great howl which whistles through the front door and down the chimney on windy days "reminds me of home. We always had a howl like that from our front doors in Minnesota." The Mondales plan to invite people, in small groups, on an individual basis to see the house.