Democrat Harry R. Hughes was endorsed for governor of Maryland yesterday by three major newspapers while the Democratic challenger in the 8th Congressional District, Michael Barnes, won an endorsement that he predicted would result in his election Nov. 7 over incumbent Rep. Newton 1. Steers (R.-Md.)

Hughes was picked over Republican nominee J. Glenn Beall by The Washington Post, Baltimore Sun and Baltimore News-American, in editorials published yesterday.

All three newspapers praised both men but said the nod should go to Hughes because of his greater experience in state government.

The Sun called Hughes "a man of integrity, political independence and wide government experience." It said that "what really distinguishes the two men is their records of public service. Mr. Beall was a work-a-day legislator and senator (in Washington)" while Hughes, during 16 years in the state legislature, was "the major legislative craftsmen of Maryland's current tax and education-aid structures." Hughes would better understand and have more influence with the Democratic-controlled General Assembly, The Sun said.

The rival News-American said both Hughes and Beall would bring to state government "honesty and efficiency" but it said Hughes is "better equipped specifically for the job because 23 of his 50 years has been in continuous training" as a state legislator or administrator.

The Post said "it's not an easy choice>" but "on balance, we think (Hughes) is better attuned than Mr. Beall to the financial and administrative problems that we believe will pose the toughest tests for the next governor of Maryland."

Barnes was endorsed by The Post, which said that freshman Congress-man Steers had "disappointed us" by supporting "the Kemp-Roth tax-cut extravaganza" and "has squandered his time and energy in a flurry of small projects and press releases."

At a luncheon meeting with reporters and editors of The Post last week, Barnes said that The Post's endorsement "would determine who wins." He credited Steers' victory two years ago to an endorsement from The Post, and while Barnes decried such influence, he said "in a race this close, it will be the difference."

Yesterday, Barnes was ecstatic, saying the editorial had had "an incredible impact already." Volunteers making telephone calls had detected "a clear shift" to Barnes among previously undecided voters who had read the editorial, he said.

Steers could take some solace from an endorsement by The Sun yesterday, although it is not widely circulated in Montgomery County. The Sun also praised Barnes, but said "he will have future opportunities for public service. Mr Steers is the better choice now."

In other congressional races in Maryland. The Sun and The Post both endorsed Rep. Gladys Noon Spellman (D-Md.) in the 5th District and Beverly R. Byron to succeed her late husband. Rep. Goodloe E. Byron (D-Md.) in the 6th.

In the 4th District, The Sun picked Democratic challenger Sue Ward over Rep. Marjorie S. Holt (R-Md.). The Sun wrote that Hold "has not grown in three terms as she should have. Her conservatism is small-minded and narrow." Ward, who earlier was endorsed by The Baltimore Evening Sun, is "a challenger with a wealth of civic and social work experience (who) brings a refreshing mix of concerns for fiscal prudence and human need."

The Post said "we're stuck, we suspect" with Holt," "an attractive Democrat . . . has been unable to mobilize much of a campaign."

In the Holt-Ward contest, challenger Ward told a Democratic unity breakfast in Anne Arundel County yesterday that she had hand-delivered a letter to Holt in which she complained that Holt has been making statements about her that are "not correct."

Ward said Holt had misquoted her in interviews last week with The Post and The Sun.