Sean Nelson (born June 12, 1973) is an American singer, songwriter, and keyboardist, notable as the frontman for alternative rock group Harvey Danger.

Aside from Harvey Danger, Nelson has also provided vocals to Death Cab for Cutie, The Minus 5, Nada Surf, and vocals/keyboards to The Long Winters, on the independent record label Barsuk Records. He also wrote a column for Seattle, Washington alternative weekly The Stranger. In 2007, his book about Joni Mitchell's album Court and Spark was published as part of the 33 1/3 series.