The House last night overwhelmingly approved extension of the Voting Rights Act of 1965, giving Democrats and civil rights groups one of their few legislative victories this year.

The bill extends antidiscrimination laws at the polls indefinitely but gives jurisdictions covered by the act an easier way to escape its provisions with good behavior.

The 389-to-24 vote came after a coalition of Democrats and moderate Republicans brushed aside nine amendments designed to weaken the bill and eliminate the requirement for printing of bilingual ballots.

"Today, the House has made good its commitments to the major civil rights battles of the l960s," Speaker Thomas P. (Tip) O'Neill Jr. (D-Mass.) said a few minutes before the vote. "It is guaranteeing the right to vote."

With the administration's position on many provisions of the bill unclear, the extension faces an uncertain future in the more conservative Senate, which is not scheduled to begin hearings on it until at least January.

While civil rights lobbyists crowded the corridors, supporters of the extension had rolled up lopsided victories as they insisted that any amendment to the extension bill would weaken it and was unacceptable.

This tactic rankled opponents such as Rep. Daniel E. Lungren (R-Calif.), who accused civil rights groups of engaging in "emotional and moral blackmail."

The coalition of Democrats and moderate Republicans crushed opposition by ratios as great as 3 to 1 as the extension moved toward passage. Key provisions of the bill do not expire until next August, but civil rights groups had pressed for early House action because they fear Senate opposition.

The Voting Rights Act, passed at the height of the civil rights movement, banned the use of literacy tests, poll taxes and other devices used to keep blacks and other minorities from voting. States with a history of voting rights discrimination are required to receive "pre-clearance" from the Justice Department for any changes in state or local election laws.

Since that time, the number of blacks registered to vote in the South has climbed from 29.3 percent to 56.6 percent in 1980, and the number of blacks holding elective office from less than 100 to 1,813. This has led to pressure for relief from pre-clearance conditions, which now apply to Alaska and eight southern states, including Virginia, and parts of 13 other states.

To meet this pressure, the House Judiciary Committee worked out compromise "bailout" procedures that would allow jurisdictions to avoid being covered if they could show no voting violations for 10 years.

To qualify for a bailout, a state must prove it has used no literacy test or similar device, has fully complied with pre-clearance requirements, has not been found guilty by a court of abridging the right to vote, has not had federal examiners sent in to enforce voting rights and has engaged in constructive efforts to eliminate intimidation.

Votes were taken with little guidance from the White House. President Reagan initially said he favored extension of the act but only if its coverage were expanded to include the entire nation. He abandoned that position in August, saying such action would make the law too cumbersome to enforce.

Beyond that, the administration has not taken a position on the House bill, or its specific provisions. A Justice Department report on the bill, which was to have been delivered to Reagan by last Thursday, has been delayed.

There was almost no debate yesterday about the need for the bill. Instead, major challenges were directed at the bill's bilingual and bailout requirements.

The test vote on the bailout came on an amendment offered by Rep. M. Caldwell Butler (R-Va.), one of the bill's most outspoken critics. The amendment would have given authority for bailouts to three-judge circuit court panels instead of the U.S. District Court here.

Butler argued that the change would save local jurisdictions the expense of traveling here to try cases and dispel "the unvoiced argument that you can't trust the impartiality" of federal courts in the South.

House Judiciary Committee Chairman Peter W. Rodino Jr. (D-N.J.) charged that Butler's tactic was similar to those used by opponents of civil rights legislation for decades and that the only way to ensure impartiality in voting cases is to keep jurisdiction in Washington.

The amendment was rejected, 272 to 132, after three hours of debate.

The second key challenge came hours later on an amendment by Rep. Robert McClory (R-Ill.) that would have eliminated a requirement to conduct bilingual elections in areas with non-English speaking populations of more than 5 percent.

McClory and others argued that this posed an unreasonable expense and that the extension of the provision was not necessary since the bilingual provisions in the act do not expire until 1984. It lost, 283 to 193.

Rep. Mickey Leland (D-Tex.) took the wind out of the sails of the bilingual opponents by addressing the House in Spanish at the end of more than two hours of debate.

"Even though you can't understand what I'm saying, maybe you can understand the hypocrisy of rejecting citizens just because they speak only Spanish," he told the House.