Tube drivers caught video-recording their journey and posting them on the internet could face disciplinary action, London Underground has warned.
Some clips found on the website date back to 2003
Managers have warned that drivers found contravening safety regulations while filming would be reprimanded.
The practice was uncovered by commuter Christof Delin, from Dollis Hill, north-west London, who found the video clips on YouTube while surfing the net.
Passenger watchdog groups have condemned the practice.
A search on the YouTube website found nearly 20 different clips showing footage of train drivers taken from the driver's cab.
Some have been set to music while other clips date back to 2003.
"It's not the kind of behaviour we expect from drivers," said a London Underground spokesman.
He added: "We don't think it poses a risk but we don't think they should be doing it."
Regular Tube passenger Mr Christof said: "If I see a driver recording when a train passes through I'm not going to go on that train."
"I'll wait for the next one because I feel the driver isn't focused and not doing what he should be doing."