E Jerome O'Connor, 86, an architecr who came here as coordinating architect of the Pentagon in 1941-42, died Sunday at his home in Washington.

He had maintained a private pratice in Washington since 1945. He was designer-architect of the Industrial Mart and architect of the National Grange building here.

Mr. O'Connor last work involved the design of three private houses, one in Mclean and two in Washington.

Born in White Plains, N.Y., he received a degree in architecture from Cornell Unversity in 1912.

He was associated with a number of architectural firms in New York and had his own private practice in New York City from 1920 until 1941.

During World War II, Mr. O'Connor was under contract to the federal government as field director of airplane plants and then as designing architect for chemical warfare plants.

He was a registered architect not only in Washington and New York but also in New Jersey. Connecticut, Maryland, Virginia and Kentucky. He had designed numerous churches and schools.

Mr. O'Connor was a member of the American Institute of Architects, the National Council of Architectural Registration Boards the Washington Building Congress and the Society of Architectural Historians.

There are no immediate survivors.