Franco Vasio, 70, the chef at the A.V. Ristornate Italiano in Washington for 28 years who was noted in Washington culinary circles for his Southern Italian cooking, died of cancer Wednesday at George Washington University Hospital.

Mr. Vasaio went to work at the A.V. Ristorante, which was owned by his brother, Augusto, in 1950, the year he came to Washington. He remained there until his retirement in 1978. Since then, he had assisted his son, Fiorenzo, in running Fio's Restaurant, also in Washington.

The elder Mr. Vasaio used to say that the preparation and cooking of a perfect pizza was one of the highest expressions of the art of simple cooking.

Mr. Vasaio was born in Morgantown, W. Va., to a long line of restaurateurs. When he was a boy, his family moved back to Pescara, Italy, and he grew up there. His father had owned a restaurant in Morgantown, and he had another in Pescara. It wasthere that Franco Vasaio learned his profession. He returned to the UnitedStates in 1950.

In addition to his son, Fiorenzo, ofSilver Spring, and his brother, Augusto, of Falls Church, Mr. Vasaio's survivors include his wife, Alva, of Silver Spring, where the family lives, another son, Antonio,, of Alexandria, two daughters, Maria, of Silver Spring, and Lucia Krupicz, of Erie, Pa., and three grandchildren.

The family suggests that expressions of sympathy be in the form of Contributions to the American Cancer Society.