He studied at the Athens School of Philosophy, but did not graduate. He participated as a volunteer in the Balkan Wars of 1912-13. He then enlisted in the Evelpidon School and graduated as an artillery lieutenant. He took part in the Defence movement of 1916 and was promoted in rank as a Venizelist. He participated in World War I, the Ukrainian campaign (where he was wounded) and the Asia Minor campaign. In 1924 he became a Major. He graduated from the Higher War College in 1926. In 1931 he was promoted to lieutenant colonel.

He took part in the Venizelist movement of 1935 as a division chief of staff and was discharged from the army. After the invasion and occupation of Greece by the Germans, a resistance group was organized by officers and reservists in the Parnassis area, under the name of EAS (1942).Thus Psarros became associated with this organization. The activity of this group extended throughout Rumeli and the mountainous northern Peloponnese. In September 1942 the organization came into contact with the British and was supported. In March 1943 Psarros took command of the group. He renamed the organization Constitution 5/42 in remembrance of the old glorious regiment of the Evzones.

Unfortunately the civil strife made its appearance and as a result 5/42 clashed with ELAS and Psarros was arrested. During his transfer to the headquarters they met with another ELAS battalion, the commander of which Euth. Zoulas, a retired major junior to Psarros and his rival, ordered the bodyguard to execute him. By special law the Nick. Plastiras restored Psarros posthumously and promoted him to lieutenant general, in his honour a bust was erected at the entrance of Amfissa.