Norma Lady Lewis, 90, known at one time as one of Washington's most gracious hostesses, died of cancer yesterday at Chevy Chase House in Washington, where she had lived for the past 18 months.

She was the widow of Sir Willmott Harsant Lewis, for many years Washington correspondent of The Times of London, who died here in 1950.

Lady Lewis, who was known to her friends as "Connie," had purchased a historic Georgetown house on Prospect Avenue NW in 1942 after it had stood vacant for 35 years. She spent several years restoring both the house and its garden. It was sold in 1961.

She also owned a 2,300-acre "shooting box" on the Potomac River just below Mount Vernon. Known as "Sycamore Landing," it was a haven during World War II for many of Washington's top military and civilian officials. It is now a wildlife refuge.

Lady Lewis was born Norma Bowler in Terrell, Tex., and grew up in Oklahoma. She lived in Okemah, Okla., where her first husband, Ludlow King, was a businessman. The marriage ended in divorce.

She went to France to serve with the Red Cross during World War I and came to Washington after the war. Her second marriage, to Maj. Gen. John A. Hull, judge advocate of the U.S. Army, also ended in divorce. She and Sir Willmott were married here in 1939.

Lady Lewis was the mother of three graduates of the Military Academy at West Point who served in World War II. Her eldest son, Army Col. Charles Bowler King, was killed in the Normandy invasion.

She is survived by two sons, retired Army Col. Ludlow King, of Washington, and retired Army Maj. John Bowler Hull, of Orange, Va.; a stepson, Willmott Lewis Jr., of Potomac; 11 grandchildren, and nine greatgrandchildren.