Maryland Acting Gov. Blair Lee III poured nearly $250,000 of his own money into his unsuccessful primary campaign for reelection, according to campaign finance reports filed here yesterday.

In the last two weeks, before the Sept. 12 primary, Lee lent his campaign $135,000 in three installments, according he had listed himself as the source of three other loans totaling $110,000, of which $30,000 had in turn been lent to him by a friend he refused to identify.

The extent of the personal campaign investment by Lee, scion of one of America's oldest and most patrician families, is unprecedented in Maryland gubernatorial politics. Ultimately, it all came to nothing when Lee lost the nomination to former state transportation secretary Harry R. Hughes in a stunning upset.

As the campaign drew to a close, Lee spent $120,000 on television ads and distributed $85,000 in so-called "walk-around money" to local party organization to get out the vote. Hughes, meanwhile, successfully sold himself to the voters with only $43,000 spent on broadcast ads and nothing for election day workers.

Cummulative totals yesterday showed the Lee campaign had raised about $950,000 - including $27,000 in loans, mostly from Lee - compared to $510,000 for Baltimore County Executive Theodore G. Venetoulis, just under $250,000 total for Hughes and about $120,000 for Baltimore City Council Chairman Walter S. Orlinsky in the primary race for governor.

Hughes and his Republican opponent, former U.S. Sen. J. Glenn Beall, were both looking toward the November general election yesterday as aides filed their contribution and disbursement reports for the four weeks ending Sept. 29.

Campaign managers Mike Canning, for Hughes, and George Beall, for his brother, J. Glenn, both set campaign budgetary goals of $300,000 yesterday for the weeks remaining until the November election.

"After a primary deficit of $40,000 or $50,000, we're almost starting from scratch," Canning said. Last week, which was not included in yesterdays filings, saw "no great shakes, no big surge," Canning said.

The Hughes campaign raised $71,563 in the two weeks before the September primary, compared to $175,763 before that. The last reporting period included about a dozen $1,000 contributions, as well as a post-primary in kind contribution of 300 "plastic imitation straw hats" valued at $180 from Lee's campaign.

Canning said the Hughes campaign expects a large financial boost from a $100-per-ticket fund raiser featuring President Jimmy Carter Oct. 18 at Baltimore Civic Center.

"Our campaign is not exactly flush by any means because of the tremendous financial costs up front you run into," George Beall said. "You have to pay a $100 deposit for each telephone."

Beall's campaign, which had raised only $38,000 by the end of August, added $95,882 in September but still found itself about $7,000 in the red. The largest single amount in Beall's war chest was in $28,800 in receipts from the Maryland GP's fund-raiser attended by former President Ford June 13, two weeks before Beall announced he was a candidate for governor.

Beal fund-raisers are scheduled for Hagerstown, Montgomery County, Baltimore, Annapolis and "probably" on the Eastern Shore. "The campaign is paying for itself as it goes," George beall said.

Beall's latest list include two dozen contributions of $1,000, and especially strong support from businesses and individuals in his own Allegheny County. Hughes' report listed $1,000 donations from the candidate himself from defense secretary Clark M. Clifford and from 10 others.