He was born in Messini in about 1870, and entered military service after studies in the Hellenic Army's NCO School.

In the subsequent Allied intervention in the Russian Civil War, he participated in the Greek expeditionary corps in the Crimea in 1919.

On 22 October 1923, along with major general Georgios Leonardopoulos, and the support of royalist officers, he launched the failed Leonardopoulos–Gargalidis coup d'état attempt.

He was captured by loyalist forces near Mount Kithairon, and condemned to degradation and death by a field military tribunal on 15 November, along with Leonardopoulos and the colonels Avrampos and Nikolareas.

Following various appeals, including by Pope Pius XI, for clemency, the sentence was commuted; Gargalidis was amnestied and removed from the army.