Petre Andrei (June 29, 1891–October 4, 1940) was a Romanian sociologist, philosopher and politician.
Born in Brăila into a family of low-ranking civil servants, Andrei attended Nicolae Bălcescu High School from 1902 to 1910. He then moved to Iași, where he enrolled in the literature and philosophy faculty of Iași University, graduating in 1913. While a student, his mentor was Ion Petrovici. He continued his education in Berlin, where he audited a seminar on logic and history of philosophy, and in Leipzig. Returning home when the war broke out, he volunteered for service, in spite of being exempt due to the fact that his father was deceased. He was assigned to an infantry regiment in March 1915, and from July to September 1916, during which time Romania entered the war, he attended the reserve officers' school in Târgoviște. He was sent to another regiment, effective November, and distinguished himself in the battles at Oituz, Slănic and the Cașin valley. For his acts of bravery, he was awarded the Order of the Star of Romania, the Order of the Crown and War Cross with Bars.
In 1918, he defended his thesis, Filosofia valorii, at Iași, receiving the title of doctor in philosophy. Initially a high school teacher, he was on the faculty of several Iași institutions: the National College, the Military High School and the Orthodox High School for Girls. He was then a substitute professor of history of philosophy in the sociology department of Iași University, becoming a full professor in 1922. The appointment to this post, left vacant upon the departure of Dimitrie Gusti, prompted a fierce battle within the faculty that drew the attention of the contemporary press. One wing, led by Ion Găvănescul, pushed for Garabet Aslan; another, which Petrovici headed, wanted Andrei. The latter faction was joined by Garabet Ibrăileanu when Petrovici promised to support Mihai Ralea's appointment after the latter's return from France; and by the new dean, Traian Bratu, a bitter adversary of Găvănescul and his ally Oreste Tafrali.