Jessie Hendrick Hardie Bartlett, 71, a representative of the Federal Bar Association at the Law of the Sea Conference in Caracas in 1975, died of cancer Wednesday at Georgetown University Hospital.

Mrs. Bartlett, who had maintained a home in Washington since 1962, was a lawyer in both the United States and Britain. She was born in Philadelphia. A graduate of Bryn Mawr College, she studied law at Oxford University in England. She practiced in London for several years and then moved to New York, where she also practiced law, having earned doctorates in law from New York University.

In 1933, she married William Huger Hardie, who died in 1959.In 1962, she married Frederick Pearson Bartlett, a former U.S. ambassador to the Malagasy Republic, who died in 1970.

After moving to Washington, Mrs. Bartlett worked as an examiner in the U.S. Copyright Office. She also was active in the Foreign Service Women's Association and organized a seminar on foreign service life for its members. She was a member of the Washington Foreign Law Society, the Washington branch of the English Speaking Union, and the Bryn Mawr Club of Washington.

Survivors include two children, Robin Hardie Griffiths, of Arlington, and William Huger Hardie Jr., of Mobile, Ala.; a sister, Lady Hitchman, of London, and four grandchildren.