Career
Le Havre and Beauvais
Diallo started playing football for the reserve team of professional club Le Havre in the Championnat de France amateur, the 4th tier of French football. After spending just half a year at the side he moved on a free transfer to Championnat National side AS Beauvais Oise. With Beauvais, Diallo played 22 games and scored once to wrap up the 2009-2010 Championnat National season.
South. du Pays de Charleroi
At the start of the 2010-2011 season, Diallo joined Belgian side Sporting Charleroi in the Belgian Pro League.
The 2010-2011 season marked the first year for Diallo in top-flight football. Although he only amassed six appearances, while being subbed in a further five, it marked a pivotal point in his career.
At the end of the season, Charleroi finished 16th and were relegated to the Belgian Second Division. Dijon
On July 2011, Diallo moved to Dijon on a free transfer for the 2011-2012 Ligue 1 season.
Ajaccio
On June 18, 2015, Diallo signed with Air Corps Ajaccio from Dijon Foreign and Commonwealth Office.