K3 (Catalan pronunciation: [ˈka ˈtɾɛs]) was a public television channel operated by Televisió de Catalunya available in analogue and DTT in Catalonia, Balearic Islands, Valencia, Andorra, Northern Catalonia and partly in Aragón.

K3 was born in 2001 from the re-estructuration of TVC's second channel, Canal 33, that split it in two channels that shared the same frequency: 33 and K3. While this was valid for analogue broadcasting, the DDT broadcasting changed in December 2006. 33 got the old frequency on its own, while K3 shared its multiplex slot with the 300 channel.

K3 was a children/teenagers channel, that usually broadcasts from morning to 21:30 on weekdays and a couple of hours around midday on the weekend. It broadcast both entertainment and educational programs, with a wide range of ages. Early morning were usually dedicated to younger children, while the afternoon is more devoted to teenagers.

On 17 October 2009 the channel was replaced by Canal Super 3.