Matthew Fusillo, 58, a retired government microbiologist and associate professor of pathology at the George Washington University Medical School, died of arteriosclerotic heart disease Sunday at his home in Temple Hills, Md.

Mr. Fusillo was a supervisor with the antibiotic research laboratory at Walter Reed Army Hospital from 1948 to 1955. He then spent nine years as research microbiologist and chief of the section for infectious diseases at D.C. General Hospital.

From 1964 until retiring from the government in 1976, he was a researcher with the Veterans Administration Hosital in Washington. For the past four years he had been a microbiology consultant

His career included work in tissue culture techniques to evaluate antibiotic actions on cells. In addition to helping develop sensitivity tests, he worked on the immunology of tuberculosis and staphylococcal infections.

He was a clinical instructor of microbiology at the George Washington University medical school from 1959 to 1961, then was an associate professor of pathology at the medical school from 1973 to 1976. He also had taught at the Graduate School of the Department of Agriculture.

Mr. Fusillo was a native of New Jersey and serveed in the Army Air Force in World War II. He was a 1948 graduate of the University of Maryland and earned master's degree in bacteriology at George Washington University.

He was a member of the American Society for Microbiologists, the American Association for the Advancement of Science, and the Washington Academy of Science.

Survivors include his wife, Alice, of Temple Hills; a son, Larry, of Pass Christian, Miss.; three daughters, Lisa, of Saratoga Springs, N.Y., Jessica, of Bethesda, and Susan, of Seattle; his mother, Frances Fusillo of Clifton, N.J., and a sister, Rachel Monego of Freehold, N.J.