Francisco Dueñas Díaz (3 December 1810 – 4 March 1884) was a Salvadorean politician and member of the Conservative Party who served as President of El Salvador from:
He was "an ardent defender of the clerical interests. Dueñas at one time had taken the vows as a Dominican, but when the convents were closed in 1829, he left the cloister and secured a papal dispensation." Under his leadership, "the clerical party was in the ascendancy and El Salvador experienced a far-reaching Conservative reaction."