O
- (Lozova City Council) Oleksiivka
- (Krasnohradskyi Raion) Oleksandrivka
- (Krasnohradskyi Raion) Odradivka
- (Bohodukhivskyi Raion) Ohultsi
- (Kupianska Miskrada) Oleksandrivka
- (Bohodukhivskyi Raion) Oleksandrivka
- (Lozova City Council) Oleksiivka
- (Bohodukhivskyi Raion) Oleksiivka
- (Kupianska Miskrada) Obukhivka
- (Bohodukhivskyi Raion) Odnorobivka
- (Kharkiv City Council) Odrynka
- (Kupianska Miskrada) Ogibnoye
- (Krasnohradskyi Raion) Ohiivka
- (Krasnohradskyi Raion) Oleksandrivka
- (Chuhuiv City Council) Ohirtseve
- (Krasnohradskyi Raion) Okhoche
- (Bohodukhivskyi Raion) Okip
- (Bohodukhivskyi Raion) Oleksandrivka
- (Krasnohradskyi Raion) Oliinyky
- (Krasnohradskyi Raion) Orchyk
- (Kharkiv City Council) Ordivka
- (Lozova City Council) Orilka
- (Iziumska Miskrada) Orlikoyarskiy
- (Iziumska Miskrada) Oskil