Vincent Autin and Bruno Boileau said “oui” in the southern city of Montpellier amid tight security.
Mr Hollande had warned he would not accept any disruption to the ceremony. The new legislation has proved controversial and sparked violent protests.
The anti-gay marriage lobby, backed by the Catholic Church and conservative opposition, argues the bill undermines an essential building block of society.
The ceremony was broadcast live on French TV.
Read more on this story at bbc.co.uk