In 1887 he graduated first in his class from the Infantry and Cavalry Officers School in Bucharest, with the rank of second lieutenant.

He became Chief of the Romanian General Staff on 2 December 1913, and served in this role until 1 April 1914.

[3] He continued to lead the 1st Army Mărășești until 11 August, when he was succeeded by General Eremia Grigorescu.

[2] After the end of the War, Cristescu served for a third and final term as Chief of the General Staff (1 April 1920 to 8 May 1923),[2] during which time he coordinated the organization of the new national Army of Greater Romania.

[1] In Bucharest, Pitești, and Slatina streets are named General Constantin Cristescu after him.