Duterte declared September 11 a "special non-working day" in the northern province of Ilocos Norte, the Marcos stronghold.
It marked another step in the rehabilitation of Marcos 31 years after he was chased into exile in the US by a popular revolt that ended his 20-year rule marked by allegations of massive corruption and rampant human rights violations.
Duterte, who considers Marcos to have been the country's best-ever president, stunned the nation last November by allowing his remains to be transferred to the national "Heroes' Cemetery" despite a widespread outcry.
On Thursday, Duterte declared September 11 a "special non-working day" in the northern province of Ilocos Norte, the Marcos stronghold.
"The Ilocano community has been annually celebrating the birthdate of the late Ferdinand E. Marcos and commemorating his life and contributions to national development as a World War II veteran, distinguished legislator, and former president," the presidential palace proclamation read.
"It is but fitting that the people of the province of Ilocos Norte be given full opportunity to celebrate and participate in the occasion with appropriate ceremonies."
Marcos was accused of embezzling billions of dollars from state coffers, with anti-corruption watchdog Transparency International in 2004 naming him the second most corrupt leader of all time, behind Indonesian dictator Suharto.
The dictator also oversaw widespread human rights abuses to maintain his control of the country and enable his plundering, with thousands of people killed and tortured, previous Philippine governments said.
No member of the Marcos clan has ever gone to prison, while his family has made a political comeback in the Philippines, with widow Imelda and their children being elected to office.
Duterte said last week that a Marcos family member had consulted him about a proposal to hand over some of its wealth to the government, later suggesting that they may ask for immunity in exchange.
Ilocos Norte will mark the 100th anniversary with a week of events including a literary and art festival and a fashion show featuring lookalikes of the late president and his widow.