The ministry filed a motion for confiscation with one of Switzerland's top courts last Friday with the aim of returning about 5.8 million Swiss francs ($6.7 million) held in a Swiss bank to the impoverished Caribbean island.
It followed the green light given by the government on February 2 after a new law easing the restitution of stolen foreign assets to home countries came into force.
"On April 29, 2011, the federal finance ministry filed a motion for confiscation of Duvalier assets blocked in Switzerland with the Federal Administrative Tribunal," the ministry said in a statement on Monday.
"If the motion for confiscation is admitted, Switzerland will return the Duvalier assets to Haiti," in line with the new law, it added.
Switzerland had announced the first stage of return process, a fresh one-year block, three months ago.
"Baby Doc" Duvalier and his followers are accused of plundering hundreds of millions of dollars of state funds during their 15-year reign.
But traces of the assets have evaporated around the world over the decades, leaving the money repeatedly frozen by authorities in a Swiss bank in a tit-for-tat court battle with the holders since "Baby Doc" was toppled in 1986.
The Swiss accounts are held by the opaque Liechtenstein-based Brouilly foundation, which is tied to the Duvalier family, according to authorities. Haiti's former strongman has denied that he owns the money.
Duvalier, who was accused of torture and murder during his presidential rule, returned from exile to Haiti in January this year, where he faces charges of corruption, theft and misappropriation of funds.
Swiss officials have said they want the money to be used for projects to tackle poverty.
Haiti's president-elect, Michel Martelly, was quoted as saying in a newspaper interview last month that he was considering an amnesty for former leaders Jean-Bertrand Aristide and Duvalier to promote reconciliation.