Mario E. Campioli, 70, retired assistant architect and director of architecture at the U.S. Capitol who helped restore several government buildings and historical sites, died Thursday at Georgetown University Hospital. He had a lung ailment.

Mr. Campioli, who was born in Parma, Italy, came to this country in 1911 and settled in New York City. He graduated from Columbia University in 1930 and received a degree in architecture from New York University in 1937.

In 1940, he joined Eggers and Higgins, a New York architectural firm. While there, he helped design several Washington buildings, including the Dirksen Senate Office Building, the National Gallery of Art and the Red Cross Building.

Mr. Campioli was made the director of architecture at Colonial Williamsburg in 1949. During his eight years there, he assisted in the restoration of Tazewell Hall in Newport News, Va., and directed the Van Corlandt Manor Project in New York for the Rockefeller family.

In 1957, Mr. Campioli came to Washington as a partner in the architectural firm of DeWitt, Poor & Shelton, where he was office manager and project director for the West Front extention of the Capitol.

Two years later he was named assistant architect of the Capitol. During the 1960s, Mr. Campioli was the architect in charge of restoring the original Senate and Supreme Court chambers of the Capitol. For this work, he received the First Design Award of the Washington Metropolitan Chapter of the American Institute of Architects.

He retired last year.

Mr. Campioli's other honors included the Special Service Award of the American Registered Architects, the Michelangelo Award from the Columbus Sons of America and an award from the D.C. Council of Engineering and Architectural Societies.

Mr. Campioli was a fellow of the Washington chapter of the American Institute of Architects and a member of the Society of Architectural Historians, the D.C. Fine Arts Commission, the board of consultants for the Old Georgetown Act, the D.C. Chapter of the Producer's Council, Inc., and the Allied Professional Membership of the National Sculpture Society. He was president-elect of the board of trustees of the American Registered Architects.

Survivors include his wife, Margaret, of McLean; three daughters, Genevieve Kemp of Sterling, Elizabeth Lovewell of Chantilly, Va., and Margaret Dement of Tucson; a son, Carl, of Falls Church; four sisters, Alberta Stamoulis of Westwood, N.J., Mary Tait and Anne Tholen, both of McLean, and Rose Schwiesow of Lodi, Calif., and 12 grandchildren.

The family suggests that expressions of sympathy be in the form of contributions to the Vincent T. Lombardi Cancer Center, Department of Medical Onocology, c/o Philip Shein, M.D., at Georgetown University.