Kateryna Serhiivna Prokopenko (Ukrainian: Катерина Сергіївна Прокопенко; born 1995) is a Ukrainian illustrator, public activist, and volunteer.

[3] Before Russia's full-scale invasion of Ukraine, she worked as an illustrator[3] (creative pseudonym — "Koza rohata"[6]).

[2][4][7] On May 11, 2022, Kateryna Prokopenko and Yuliia Fedosiuk met Pope Francis in the Vatican and addressed him with a plea to help in saving Ukrainian defenders from "Azovstal" in Mariupol in Donetsk Oblast.

[8][2] After the Ukrainian servicemen were captured by the Russians, Kateryna, together with other "azovtsi" (Azovian) families, put all their efforts towards returning them home.

[9][10][11][12][13][4] March 23, 2023, Prokopenko filed a petition on the president's website asking to dedicate the day of May 20 to commemorate the defenders of Mariupol.