Joseph M. English Jr., 61, director of the Forensic Sciences Laboratory, Inc., died yesterday at Washington Hospital Center after a heart attack.

A retired special agent with the FBI, he had established the laboratory in 1975 after serving for nine years as director of the forensic sciences laboratory of the Institute of Criminal Law and Procedure at Georgetown University.

Mr. English joined the FBI laboratory in Washington in 1942. He was trained there as a document examiner and served in that capacity until retiring in 1966.

At the Georgetown laboratory, he directed a school to train document examiners, teaching students from this country and abroad. It was one of the few schools of its type in the world.

Mr. English also examined documents and did research work in ink analysis and other areas.

The laboratory he established later is a nonprofit corporation that works on document examinations and other forensic sciences for use as trial evidence.

Since 1968, Mr. English had been an adjunct professor at the Georgetown University Law Center, where he taught a course on expert testimony.

He also had been an adjunct professor, teaching a course in forensic sciences, at the American University Center for the Administration of Justice since 1969.

Born in Philadelphia, Mr. English received a bachelor's degree in journalism and philosophy from St. Joseph's College there. He was a writer and cartoonist with the Philadelphia Evening Public Ledger from 1936 until joining the FBI here.

He earned a master's degree in adult education from George Washington University in 1967.

Mr. English was a member of the American Society of Questioned Document Examainers and the American Academy of Forensic Sciences.

He is survived by his wife, Dorothea M. and a son, Thomas F., of the home in Silver Spring; another son, Joseph M. III, of Kensington; a daughter, Jeanne Marie Sullivan, of SIlver Spring, and seven grandchildren.