Discovery HD is the international name of the high-definition television channels from Discovery Communications.

The international Discovery HD (now Discovery HD World in Asia-Pacific markets) first launched in Korea on February 2005 as a programming block. In December 2005, Discovery HD Japan and Discovery HD Canada (since renamed Discovery World HD) launched as 24-hour channels, becoming the 100th and 101st Discovery networks overall. After this, Discovery HD expanded into other markets as follows:

The first American HD Discovery channel has the name Velocity and launched in June 2002.

A second Discovery HD channel, called 'Discovery Channel HD', was launched in the USA on Dish Network the week of August 13, 2007. This new channel simulcasts the main Discovery Channel feed, but airs high-definition versions of programming when available. It is also available on DirecTV and various U.S. cable operators along with fellow sister high definition version networks TLC, Animal Planet, and Science Channel.