It's her third visit to Ukraine's capital since Russia invaded in February.
Fresh from her state of the union speech, EU chief Ursula von der Leyen has travelled to Kyiv to reinforce the bloc's support for Ukraine.
She is due to meet Ukraine's president Volodymyr Zelenskyy and Denys Shmyhal, the country's prime minister.
The meeting was expected to focus on how to unite Ukraine and Europe to progress the country's accession to the European Union.
France's president Emmanuel Macron has said it could take Ukraine "several decades" to join the bloc.
Ukraine will likely ask for more financial and military support. After its counter-offensive, which has taken large swathes of territory in the northeast, Kyiv is keen to show that any extra weapons would have tangible results in the war.