Under the Iron Sea is the second album by rock band Keane. It was launched in June 2006.

There is a version with a bonus DVD. This includes videos and demo versions of songs.

The title of the album comes from the phrase "I lost my heart. I buried it too deep under the iron sea," of the eighth (8th) song, "Crystal Ball".

In its first week sold 222,297 copies. It was #1 in UK and #4 in US.

The album had sold 1,000,000 copies to date.