John P. Allan, 71, former assistant to the director of the University of Cincinnati Medical Center, died of pneumonia and congestive heart failure April 19 at the Sharon Nursing Home in Olney. He had lived there for the past 2 1/2 years.

He had retired from the medical center in 1972, and a year later moved to Rossmoor Leisure World in Silver Spring.

Mr. Allan had lived in Washington from 1953 to 1955 while working for the Canadian Defense Department's liaison office here. He then went to the University of Cincinnati Medical Center as assistant administrator of the General Hospital, which is part of the center.

Born in Scotland, he grew up in Edinburgh. He later moved to Canada, and earned a degree in Commerce from McGill University in Montreal. During 25 years with the McColl Frontenac Oil Company, he lived in many major cities in Canada.

During World War II, Mr. Allan served in the Pacific with the Winnipeg Gremadiers. From the mid-1940s until 1951, he was director of a subsidiary of McColl Frontenac in Trinidad.

A 32d degree Mason, he was also a member of the St. Andrew's Society here.

He is survived by his wife, Catharine F., of the home in Rossmoor; three daughters, Helen Hobbs, Heather Bianco and Roberta Allan, and a brother, Thomas, all of Victoria, British Columbia; two stepsons, Berry Wright, of Silver Spring, and Jack Wright, of the home, and 10 grandchildren.