Dr. Thomas F. Collins, 75, a physician in the Washington area for 46 years, died Wednesday at Providence Hospital following a heart attack. He lived in Hyattsville.

Dr. Collins, who was born in Washington, graduated from St. John's College High School. He then earned bachelor's and master's degrees in biology at Catholic University. He took his medical degree at Georgetown University in 1933 and did his internship at the old Gallinger Hospital, now D.c. gEneral.

Dr. Collins established a private practice in general medicine in 1934. He kept his offices in Washington until 1968, when he moved them to Hyattsville. He continued to practice until his death.

For several years, he was chief of staff of Providence Hospital and was closely associated with the Daughters of Charity, who operate that facility.

He was a member of the American Medical Association and other professional organizations.

In 1957, Dr. Collins was made a Knight of St. Gregory by Pope Pius XII for his services to the Catholic Church. He was a member of the parish of St. Aloysius Church in Washington.

His wife, the former Nellie E. Salley, died in 1976.

Survivors include two daughters, Mary Widmayer and Margaret Ervin, both of Annapolis, two sons, Thomas F. X., of Chevy Chase, and Patrick J., of Chicago, and 10 grandchildren.