Col. Mamady Doumbouya, who has ruled since overthrowing the country's first democratically elected president in 2021, announced the vote during an end-of-year speech late Sunday.
He gave no date for the referendum.
"In the new year, a new constitution which resembles us and brings us together will be submitted to a referendum," Doumbouya said.
He promised a constitution "approved by the people and which is not a copy and paste but a constitution, which draws inspiration from the past to together build our future."
Doumbouya also said that people appointed by the state will soon be named to lead municipal councils, which were elected in 2018 and whose mandates end in the first few months of the year.
Nearly all the councils are currently headed by officials from parties of the ousted civilian ex-president Alpha Conde or former prime minister Cellou Dalein Diallo which are critical of the military leadership.
Doumbouya said the announcements were due to a wish to "continue the considerable efforts to return to constitutional order through the organization of free, democratic and transparent elections" respecting the timetable for a transition back to civilian rule.
Conde took office in 2010 after decades of authoritarian rule.
But he came under increasing fire after pushing through a constitutional reform that critics had argued was designed to allow him to run for a third term.
After taking power, Doumbouya, under international pressure, promised to hand the reins of government back to elected civilians by January 2026.
The September 2021 coup is among a string of putsches and attempted coups in West Africa since 2020.
Forum