Pietro Frugoni (Brescia, 21 January 1851 – Brescia, 10 July 1940) was an Italian General of the Kingdom of Italy who actively participated in the World War I, especially in the first four Battles of the Isonzo.
Appointed Lieutenant general in 1906, he received command of the I Special Corps in Tripoli during the Italian-Turkish War. In September 1912 he won the Battle of Zanzur, but was later recalled to Italy.
At the entering of Italy in World War I, he commanded the Second Army during the first four Battles of the Isonzo (June 1915 - December 1915). When The Austro-Hungarian Army launched the surprise Trentino Offensive in May 1916, Frugoni was appointed commander of the newly established 5th Italian Army to stop their advance. By mid June he was dismissed by Cardona.
He went into the reserve and wasn't recalled by Cardona's successor, Armando Diaz.
Many of his former subordinates, like general Ezio Reisoli, were critical of him in their memoires.