Mayor Marion Barry yesterday ordered a major shake-up of his administration, including the reassignment of Jose Gutierrez, head of the Department of Administrative Services, and Gladys W. Mack, director of policy and program evaluation.

Mack, a longtime Barry aide and the city's representative on the Metro transit agency board, will become a general assistant to the mayor. Gutierrez, a former personnel director, will take Mack's old job in policy evaluation. William Johnson, deputy public works director, will become acting director of administrative services.

Also, D.C. Inspector General Joyce Blalock, who headed the internal investigation of the troubled Department of Employment Services, has resigned to accept a post as inspector general of the U.S. Government Printing Office.

Vernon S. Gill, general counsel to the D.C. police department, will replace Blalock as acting inspector general.

The District Building has been rife with rumors of a shake-up for weeks, with much of the attention focused on Gutierrez, whose leadership of the large administrative services department had become a target of criticism.

City Administrator Thomas Downs was displeased with Gutierrez's performance, according to a source in the department, particularly his oversight of the Real Property Administration and the negotiations for the lease of buildings.

"Jose and Tom have tangled on occasion . . . but the mayor has told Jose he values his judgment and innovativeness," the aide said.

Neither Gutierrez nor Downs could be reached late yesterday.

In announcing the changes late yesterday, Barry described them as "mid-term personnel adjustments" that were "part of my continuing efforts to strengthen District government operations and to adjust staffing patterns to meet the complex needs of my office."

Johnson, the former director of the old D.C. Department of Environmental Services, said yesterday that Barry shed little light on what changes, if any, he wants in the Department of Administrative Services.

"The mayor asked me if I'd like to go back to cabinet-level rank, I told him yes, and he told me he had an opening," Johnson said.

Barry said he accepted Blalock's resignation reluctantly, and said the inspector general's office under her leadership "is now universally recognized and respected for its high standards of competence and integrity."

Last year, Blalock supervised an audit and review of the Department of Employment Services that turned up information concerning Ivanhoe Donaldson, former director of the agency and the mayor's closest political adviser. The evidence was turned over to a federal grand jury, which currently is investigating the matter.

In his announcement, the mayor stressed that Blalock had been sought out by the Government Printing Office for her new job. "She will be very difficult to replace."

Blalock could not be reached for comment.

Mack, a former D.C. budget director, has headed the Office of Policy and Program Evaluation since January 1983. Early this year, she was elected to a one-year term as chairwoman of the Metro Board, becoming the first woman to hold that post.

In moving into the mayor's fifth-floor executive office complex, Mack apparently will assume some of the functions of a chief of staff.

"I'm going to be helping to manage the workload," she said. "As a senior person, I'll be available to expedite the decision making. I'll be trying to make sure there is as much resolving of issues before they get to the mayor's desk."

Barry tried earlier in his administration to install a chief of staff, Clifton Smith, a former aide to D.C. Del. Walter Fauntroy, but the experiment didn't work. Smith now serves as secretary to the District of Columbia.

Gutierrez, the first Hispanic named to a Barry cabinet post, took over as director of the Department of Administrative Services in May 1984. Previously, he had been director of the Office of Personnel and a special assistant to the assistant city administrator for governmental operations. Prior to coming to the city, Gutierrez served as a staff assistant to former Rep. Herman Badillo (D-N.Y.)