Kosmos 1669 (Russian: Космос-1669) was a Progress spacecraft used to resupply the Salyut 7 space station.

Kosmos-1669 was launched by a Soyuz-U carrier rocket from Site 1/5 at the Baikonur Cosmodrome, at 13:05 UTC on 19 July 1985.

The spacecraft docked with the aft port of Salyut 7 at 15:05 UTC on 21 July 1985.

Following undocking on 28 August 1985, it moved away from the station, before returning and redocking to test the reliability of the docking system.

[1] Alternatively, it could have been given the designation as it was used to test modifications that would be used on future Progress missions.