Dr. Ethel Mercedes Sutton Weiseger, 74, a physician in Washington for almost 50 years, died of cancer Sunday at Washington Hospital Center.

Dr. Weiseger was born in Washington. She graduated from the old Dunbar High School and then went to Howard University, where she earned a bachelor of science degree in 1927. She graduated from Howard Medical School in 1932 and did her internship at the old Freedmen's Hospital, now Howard University Hospital.

She then entered private practice and continued in it until shortly before her death. She also had been the examining physician at the old National Training School for Girls here and at the Southwest Community House. She had been a clinical instructor in pediatrics at the Howard University Medical School.

Dr. Weiseger was a member of the board of the Ionia Whipper Home for Unmarried Mothers and a member of the Medico-Chirurgicial Society, the National Medical Association, the Urban League, the NAACP, the Jack and Jill Club, Inc., an organization for the benefit of children, Les Amis, a mothers' group, and the Howard University Medical School Alumni Association.

She also was a member of the parish of St. Augustine's Catholic Church and its Sodality and then of the Sacred Heart Church and its Sodality.

A son, Arthur Eugene Weiseger, died in December.

Survivors include her husband, James Arthur Weiseger, of Washington, and two grandchildren.

The family suggests that expressions of sympathy be in the form of contributions to the D.C. Chapter of the American Cancer Society, 1825 Connecticut Ave. Nw, Washington, D.c. 20009.