Kostiantynivka is a village in Ukraine, in Khotin settlement hromada, Sumy Raion, Sumy Oblast, Ukraine. Until 2016, the local government body was the .
The village of Kostiantynivka is located 1.5 km from the left bank of the Sinyak River. At a distance of 2.5 km are the villages of Kindrativka and . The village is located on the border with Russia.
The originates on the western outskirts of the village.
On June 12, 2020, in accordance with the Resolution of the Cabinet of Ministers of Ukraine No. 723-r "On the Determination of Administrative Centers and Approval of Territories of Territorial Communities of Sumy Region", it became part of the Khotin settlement hromada.
On July 19, 2020, as a result of the administrative-territorial reform and liquidation of the , the village became part of the newly formed Sumy Raion.
On July 14, 2024, the village was shelled by Russian forces. 6 explosions were recorded, which probably came from a helicopter.
Russian forces first entered the village before 29 May 2025. The village was captured by Russian forces on 29 May 2025. On 30 October 2025, Ukrainian forces moved into the east of the village, recontesting Kostiantynivka.
According to the 2001 Ukrainian census, the village's population was 246 people. The main languages of the village were:
The following were born in the village: