Local media reported that the dismantling of the monument to Russian Empress Catherine II started on the morning of Dec. 28.
The Odesa city council confirmed it later in the day, saying that the monument would be transferred to the Odesa Fine Arts Museum.
Local authorities agreed to dismantle the monument on Nov. 30, following an online vote by Odesa residents that approved the decision in early November.
The monument to Catherine II and other founders of Odesa is a major landmark of the city.
It was erected in 1900, when Odesa was part of the Russian Empire, and dismantled by the Bolsheviks in 1920. It was restored by the city council in 2007.
Catherine II, who ruled in 1762-1796, has a controversial reputation in Ukraine because she promoted Russian imperialism and liquidated two autonomous Ukrainian entities - the Zapirizhzhian Sich and the Hetmanate.
Pro-Ukrainian activists have advocated dismantling it for years, while pro-Russian activists have opposed the move.
Odesa Mayor Hennadiy Trukhanov, a former lawmaker from ex-President Viktor Yanukovych's Party of Regions, had previously targeted pro-Russian voters.
However, he changed his rhetoric after Russia launched its full-scale invasion of Ukraine on Feb. 24.
The campaign to dismantle monuments linked to Russia kicked off in Ukraine after the full-scale invasion began.