The Daewoo Precision Industries K4 (Korean: K4 고속유탄기관총; Hanja: K4 高速榴彈機關槍) is a 40×53mm high-speed automatic grenade launcher in use with the Republic of Korea Armed Forces.

The K4 was developed as a complement to the K-201 hand-held grenade launcher (attachable to the K2).

[3] It has a weight of 34.4  kg (empty, without accessories) and can fire up to 325 rounds per minute with a firing range of 1.5 km.

When needed to be used during night operations, a KAN/TVS-5 night vision scope can be attached onto the receiver.

[2] The K4 is said to visually resemble the Mk 19 AGL.