It`s probably Aspen Green Pearl (6S7) or Woodland Pearl (6R1) . Check on this link to be sure. If it`s the color you saw, it was a Generation 2 Toyota Avalon (2000 to 2004). Hope it help you.
http://toyotareference.com/avalon#AV
*Edit* Nima, why are you copying and pasting my answer, you are not able to make one by yourself?? You should be ashamed of it. You`ll be reported for that.