With just a few days left on the New York set, the actress revealed she will miss the cast and crew of the US TV series.
"It's been such a delight to be a part of this show," she wrote on MySpace. "Two days left of my shoot on Ugly Betty - I am quite sad to have to leave the wonderful cast and crew behind. It's always sad to leave people that you get close to."
Lohan plays a mean former classmate of Betty (America Ferrera) on the show.
She recently denied rumours that she is to marry girlfriend DJ Samantha Ronson.