Robert H. McKinney, nominated by President Carter to ahead the Federal Home Loan Bank Board, is likely to face conflict-of-interest charges stemming from his chairmanship of an Indianapolis savings and loan association.

His nomination, which was announced Thursday, has also been opposed by civil rights and consumer groups who charge that First Federal Savings and Loan of Indianapolis has shunned lending to the inner city.

McKinney and the savings and loan association are being investigated by a House subcommittee as part of its probe of conflicts of interest in the S&L industry.

McKinney is senior partner in a law firm that does business with the S&L he heads and also is an officer in another supply company that has a life insurance subsidiary.

McKinney, a classmate of the President's at the Naval Academy, headed the Carter campaign in Idiana.

Sen. William Proxmire (D-Wis.), chairman of the Senate Banking Committee which must hold hearings on the McKinney nomination, has said he has reservations about McKinney and in general is opposed to having federal regulators come from the industry they are to regulate.

Rep. Benjamin Rosenthal (D-N.Y.), chairman of the House subcommittee on commerce, consumer and monetary affairs, is expected to testify against McKinney on the basis of his subcommittee's investigation. Subcommittee staffers were at the bank board yesterday combing through files on First Federal of Indianapolis.

The Senate Banking Committee will hold hearings on July 15 and 18.

The Federal Home Loan Bank Board regulates federally chartered savings and loan associations. Savings and loan associations finance most of the residential and much of the commercial construction in the country.

Savings and loans do not have as wide financial powers as commercial banks. They cannot offer checking accounts, for example, and by law most of their lending is confined to the residential housing and commercial construction field.

While McKinney's nomination may face stiff opposition from some quarters, it was applauded by the savings and loan industry.

John A. Hardin, president of the United States League of Savings Associations, said McKinney "has pursued an unusually diversified career in the legal profession and the business world, particularly in the insurance business. In each of his endeavors he is widely respected for his success and for his integrity."

Last May a coalition - including Ralph Nader, Vernon E. Jordan Jr., director of the National Urban League and Kathleen O'Reilly director of the Consumer Federation of America - wrote President Carter to ask him not to name McKinney to the bank board.

They said his nomination "and confirmation as chairperson would undermine any prospect that the FHLBB might take a positive role in the task of urban revitalization or act vigorously to eliminate conflicts of interest in the S&L industry."

There has not been a full-time chairman of the bank board since Thomas Bomar left in 1975. Garth Marston, a Republican, has been acting chairman since Bomar left.

Grady Perry, a Democrat whose term expires June 30, is the other member of the board. The third seat has been vacant since Bomar departed.

House subcommittee sources said that First Federal was not picked because the President planned to nominate its chairman to head the Federal Home Loan Bank Board.

Instead, the S&L was one of a dozen or so picked to study as part of conflict-of-interest probe Rosenthal is conducting. One of the member of the subcommittee is from Indianapolis and First Federal is the third largest S&L in the state.

McKinney and his brother E. Kirk McKinney has controlling interest in a materials supply firm. Jefferson Corp. has a life insurance subsidiary - of which both McKinneys are officers - that has done business with customers of the S&L.

The House subcommittee expects to hold hearings on conflicts of interest in the savings and loan industry late in July.