Highway M03 is a Ukrainian international highway (M-highway) connecting Kyiv with Dovzhansky on the border with Russia, where it continues into Russia as the A270.^[1] It is part of European route E40 from Kyiv to Debaltseve at which it is part of European route E50 to the border with Russia.^[2] At 844 km (524 mi), the M03 is the longest international state highway in Ukraine.

Highway M03
Автошлях М03
Route information
Part of
Length	844.2 km (524.6 mi) 858.9 km (533.7 mi) with access roads
Kyiv - Boryspil (part of E40)
Length	18 km (11 mi)
E40 (main)
Length	1 km (0.62 mi)
West end	(Kyiv) E40 M 06 E101 E95 E373
Major intersections	(Poltava) E584 (Kharkiv) E105
East end	(Debaltseve) E40 M 04 E50
E50 (Donbas)
Length	1 km (0.62 mi)
West end	(Debaltseve) E50 M 04 E40
East end	(Dovzhansky) (Sverdlovsk Raion) / E50 M 19
Location
Country	Ukraine
Oblasts	Kyiv, Kyiv, Poltava, Kharkiv, Donetsk, Luhansk
Highway system
Roads in Ukraine State Highways
← M 02 → M 05

In Soviet times the M03 was part of the M19. Today, the highway stretches through five oblasts and ends at the border checkpoint at Dovzhansky which is part of Sverdlovsk Raion (Luhansk Oblast). The route connects Kyiv and Kharkiv with the industrial region of Donbas. Part of the M03 between Kyiv and Boryspil was reconstructed into an automagistral to handle higher traffic between Kyiv and the Boryspil International Airport.

From Boryspil to Lubny, the road is a dual carriageway, thereon it continues as a single carriageway with some 2x2 sections.

Significant armed conflict has occurred on or near the eastern portions of the highway during the war in Donbas and the 2022 Russian Invasion of Ukraine.