Jablanczy graduated from the University of Paris 1 Pantheon-Sorbonne and the "Institut d'études politiques de Paris". She started her career in 1976 as a economics and teacher at Pantheon-Assas University. In 1997, she was nominated Director of the ISEG. She is also a financial markets teacher at the "École Nationale Supérieure des Télécommunications de Bretagne".