The decision by the Court of Cassation upheld earlier verdicts from lower courts in the Campania city of Salerno, ruling out a link between the vaccine and autism.
It comes amid ongoing controversy in Italy over childhood immunization, and after a surge in the number of measles cases due to parents refusing to vaccinate their children against the highly contagious disease because of concerns over autism.
There were 3,232 cases of measles between January and June this year compared to 478 during the same period last year. A six-year-old boy died of the illness in June. A doctor confirmed he had not been vaccinated against it.
According to Health Ministry data, only 85.3 percent of Italian two-year-olds had been vaccinated in 2015, well short of the 95 percent threshold recommended by the World Health Organization (WHO) to contain outbreaks.
The rise in the number of cases prompted the government to make it compulsory for children to be vaccinated against 12 common illnesses before they can enrol for state-run schools. The measure will take effect in September. Parents also face fines if their children are not vaccinated before the age of six, the school starting age.