Donald I. Hovde, undersecretary of Housing and Urban Development, has repaid the government $3,100 for improperly using a government car and chauffeur to commute from his home in McLean and to carry his family on personal errands.

Hovde's agency car and driver were used to take his wife downtown, his neighbors to the Kennedy Center, his daughter to school and his parents on a sightseeing trip to the Capitol, according to a report by HUD's acting inspector general, Paul A. Adams.

Hovde also used the car to attend a Saturday wedding, pick up his suit at a store, visit his car dealer, pick up laundry, go to the airport for personal trips and dine at private homes and restaurants, the report said.

President Reagan recently nominated Hovde to the three-member Federal Home Loan Bank Board. The Senate is expected to consider his nomination soon.

The inspector general said the trips had cost the government $6,845 in fuel costs and overtime pay for the driver, but Hovde and his attorney disputed the figures. After extensive negotiations, the inspector general dropped some of his objections and told HUD Secretary Samuel R. Pierce Jr. that Hovde should repay $3,149.

"I said I would pay whatever figure I was given by Secretary Pierce," Hovde said. "Whatever figure that was, that's the figure I paid."

Hovde said he disputed the original findings because the legal restrictions did not apply to some of the trips he made while serving as acting secretary in Pierce's absence. He said he often was working late in his office when he asked his driver to take him home or to pick up his wife for an evening function.

"It was a matter of time convenience," said Hovde, a former president of the National Association of Realtors. "One of the ironies of this whole thing is that the longer I worked, the more it cost me, because that's when the meter started to run. Is it embarrassing for me? Yes. Was it done with intent? No."

Pierce declined to take further action in the matter, saying that Hovde's use of the car "did not constitute a 'willful' violation of the statutory restrictions."

From March, 1981, through last June, the report said, Hovde used his leased Buick Le Sabre for 136 trips between his Virginia home and HUD's Southwest Washington headquarters. The trips covered 2,992 miles and cost 189 hours in overtime pay for the driver.

Although Hovde said he was not aware of the restrictions, the report said several officials had raised the issue with him. Judith L. Tardy, assistant secretary for administration, told investigators that she repeatedly warned Hovde and other top HUD officials that any personal use of their government cars could violate agency rules, the report said.

Stephen Bollinger, HUD's assistant secretary for community planning and development, agreed to repay $2,611 for using a government car for 145 trips between HUD and Union Station as part of the daily commute from his home in Baltimore. Bollinger, who could not be reached for comment, told investigators that he had not been aware that the practice violated agency rules.

Three other senior HUD officials agreed to repay nominal amounts for unauthorized use of agency cars.