After his parliamentary career ended, Bloncourt settled in Paris and worked as teacher at the Lycée Charlemagne and at the Centre national d'enseignement par correspondence. He retired in 1960. He continued to be involved in politics through minor political parties and other engagements. In 1960 he started the "Comité d’aide aux victimes de la répression" to support those who opposed the French war in Algeria. On 22 June 1968, he was one of 29 signers of a letter in "Le Monde" which condemned as undemocratic certain measures by the De Gaulle government.