The invention relates to a check valve (10) for accommodation in a channel (5) through which a fluid can flow, comprising a valve seat element (1), a valve body (2), as well as a sleeve (3), wherein the valve body (2) can be moved in the sleeve (3) in such a way that same rests on the valve seat element (1) in a first position, and is arranged at a distance from the valve seat element (1) in a second position. The valve seat element (1) has a bore hole (11) which can be closed by the valve body (2) in the first position. A spring element (4) is arranged between the valve body (2) and the sleeve (3). The spring element has a first end (41) and a second end (42), wherein the valve body (2) is retained in the first position via the spring element (4), provided that the fluid pressure present in the bore hole is less than the closing force of the spring element (4), wherein the first end (41) of the spring element (4) is connected to the valve body. The sleeve (3) has a first casing element (31) which is intended for accommodation in the channel (5). The sleeve (3) has a second casing element (32) which is intended for accommodating the second end (42) of the spring element (4). The spring element (4) is retained in a recess (33) of the second casing element (32).