Bertha (Betty) Perry, 70, a former government lawyer who was active in numerous child development programs in the Washington area, died of cancer Tuesday at Georgetown University Hospital.

Last February, the D.C. City Council passed a resolution in which it said that Mrs. Perry had "served the cause of establishing and improving day care in the District of Columbia with unusual dedication and deep commitment and is therefore worthy of the council's praise and honor."

The resolution said Mrs. Perry has worked for more and better day-care facilities for children here for more than 40 years. It noted that she had been a member of the council's advisory commission on child development facilities, and as a lawyer, had given valuable technical assistance to that body.

The council also cited Mrs. Perry for help in the drafting and passage of child care legislation in the city and her efforts to get federal funds for day-care programs.

Mrs. Perry was born in Wyomissing, Pa. She graduated from Goucher College and came to Washington in 1930 to work for the U.S. Children's Bureau. At the same time, she earned a law degree at George Washington University by attending night classes. She later was a legislative analyst with the old Social Security Board, working on public assistance programs in the states. She left government service in 1943 to rear her family.

She was a former president of the Georgetown Children's House, a founder, president and longtime board member of the National Day Care Association, and chairman of the day-care advisory committee of the old D.C. welfare department. In later years, she was a member of former mayor Walter E. Washington's advisory commission on day care.

Mrs. Perry also was secretary of the D.C. Citizens for Better Public Education and a member of the D.C. Health and Welfare Council. She was a member of the vestry at St. John's Episcopal Church and a vice president of the National Cathedral Association and chairman of its Washington committee. (The association is a national organization that raises funds for Washington Cathedral).

Survivors include her husband, Carroll, of Washington, where the family lives; two sons, Carroll III of Ipswich, Mass., and David, of Washington; a sister, Robin S. Biddison of Baltimore; a brother, Alan Smith of Southbury, Conn., and two grandchildren.

The family suggests that expressions of sympathy be in the form of contributions to the Georgetown Children's House, or to St. Joseph's Episcopal Church, both in Washington.