In the video, al-Zarqawi says mujahideen in Iraq are fighting on, despite what he calls a three-year "crusader" war.
Al-Zarqawi, clad in black and a green vest with an assault rifle by his side, is also shown training with a group of masked men outdoors.
The Jordanian-born militant has previously issued messages via audio recordings.
The authenticity of the tape could not be immediately verified.
(AFP, Reuters)