A coalition of black leaders said yesterday that it is "gravely disturbed" that President Carter may be preparing to fight inflation at the expense of blacks and the poor.

Vernon Jordan, president of the National Urban League and spokesman for the group calling itself the "Black Leadership Forum," emerged from the White House after more than two hours of meetings with a warning that failure to act against unemployment "could well undermine the Carter administration."

He said that blacks and the poor "are becoming increasingly alienated from the political process" and that "unless they are given relief, it will be impossible to contain their despair or for them to sublimate their anger to the political process."

Jordan said the president, who met with the group for an hour, made no promises, and he indicated that the group heard little else to cheer it during the meetings with Carter, Vice President Mondale and top administration domestic policy officials.

The White House meetings yesterday were the clearest illustrations to date of how the president's publicly declared determination to bring inflation under control could bring him into conflict with traditionally Democratic groups.

Carter depended heavily on black votes for his election in 1976 and, once in office, initiated programs designed to reduce unemployment, a major concern of black leaders. But while the national unemployment rate declined during the last two years, the president's relations with black groups have been uneasy and have become increasingly strained as the administration focused its attention on fighting inflation.

In another sign of that strain, the Congressional Black Caucus -- which negotiated long and hard earlier this year to gain White House support for a watered-down version of the Humphrey-Hawkins "full employment" bill -- did not even bother to send a representative to yesterday's meeting.

"The feeling was that the meeting wouldn't accomplish anything," said one caucus source who asked not to be identified.

Last month, the Black Caucus sent Carter a letter praising him for supporting the Humphrey-Hawkins legislation but criticizing other recent administration economic policy decisions that it said "run directly counter to the substance and purpose" of the measure.

Joseph Lowery of the Southern Christian Leadership Conference, one of those at the White House meeting, said the group asked the president "to make unemployment a twin priority with anti-inflation."

"We are asking that he not make the poor bear the major or an inequitable burden" in the fight against inflation," he said.

"We haven't heard it all," Lowery added, but "we're deeply disturbed by what we have heard."

Yesterday's meeting was one in a series that White House officials have arranged with groups that are concerned with funding levels in the budget that Carter will present to Congress in January for the fiscal year that begins Oct. 1. The president has pledged to reduce the federal deficit to less than $30 billion and to increase defense spending. This makes domestic programs -- including many strongly supported by Democratic groups -- the most likely targets for cuts.

With reporters present for a few minutes of the meeting, Carter pledged that he will not overlook the needs of the poor in preparing the budget. But he also renewed his promise to fight inflation, which in the past he has said is his top domestic priority.

Outside the White House, Jordan later told reporters that while final budget decisions have not been made, "we were gravely disturbed that few programs are yet proposed to reduce unemployment much below 6 percent, which means up to 15 percent in the black community in general and perhaps more than 30 percent for black teen-agers."

He said blacks and the poor are willing to bear their "share" of the anti-inflation effort, but that he and the other black leaders were concerned that these groups "not become the victims of inflation."