"We reject U.S. President Trump's statement on the 1915 events dated on April 24 2019," the Foreign Ministry said in a written statement.
The statement, based on the "subjective narrative" of the Armenians, is null and void, the ministry said.
"Distortion of history by internal political opinions is never acceptable," the statement read.
On Wednesday, Trump issued an annual commemoration of the 1915 events, again using the Armenian term “Meds Yeghern" to describe the tragedy.
Successive U.S. presidents have refrained from calling the deaths of Armenians "genocide," but former President Barack Obama adopted the Armenian phrase "Meds Yeghern", or "Great Crime", to describe the tragedy, a practice repeated by Trump.
"We welcome the efforts of Armenians and Turks to acknowledge and reckon with their painful history," Trump said. "And we stand with the Armenian people in recalling the lives lost during the Meds Yeghern and reaffirm our commitment to a more peaceful world."
Turkey's position on the events of 1915 is that the deaths of Armenians in eastern Anatolia took place when some sided with invading Russians and revolted against Ottoman forces. A subsequent relocation of Armenians resulted in numerous casualties.
Turkey objects to the presentation of these incidents as "genocide," describing them as a tragedy in which both sides suffered casualties.
Ankara has repeatedly proposed the creation of a joint commission of historians from Turkey and Armenia as well as international experts to tackle the issue.