|Mission type||Optical imaging recpnnaissance|
|Mission duration||7 days|
|Launch mass||4730 kg |
|Start of mission|
|Launch date||14 October 1966|
12:14:00 GMT 
|Rocket||Vostok-2 s/n U1500-05|
|Launch site||Plesetsk, Site 41/1|
|End of mission|
|Landing date||21 October 1966, 06:14 GMT|
|Reference system||Geocentric |
|Perigee altitude||180 km|
|Apogee altitude||312 km|
|Epoch||14 October 1966|
Kosmos 129 (Russian: Космос 129 meaning Cosmos 129) or Zenit-2 No.33 was a Soviet, first generation, low resolution, optical film-return reconnaissance satellite launched in 1966. A Zenit-2 spacecraft, Kosmos 129 was the forty-second of eighty-one such satellites to be launched and had a mass of 4,730 kilograms (10,430 lb).
Kosmos 129 was launched by a Vostok-2 rocket, serial number U1500-05, flying from Site 41/1 at the Plesetsk Cosmodrome. The launch took place at 12:14 GMT on 14 October 1966, and following its successful arrival in orbit the spacecraft received its Kosmos designation; along with the International Designator 1966-091A and the Satellite Catalog Number 02491.
Kosmos 129 was operated in a low Earth orbit, at an epoch of 14 October 1966, it had a perigee of 180 kilometres (110 mi), an apogee of 312 kilometres (194 mi), an inclination of 65.0°, and an orbital period of 89.4 minutes. After seven days in orbit, Kosmos 129 was deorbited, with its return capsule descending under parachute, landing at 06:14 GMT on 21 October 1966, and recovered by Soviet force.