A yellow JCB worth £4,000 was stolen from a site in Crowborugh on Friday morning (Friday February 21).
Them mini JCB 801.4 digger was taken from Bright Lane at about 8am.
Sussex Police said the crime was reported at 7.40pm the same day.
The digger had a postcode BN266QY painted in black on the roof.
Anyone who saw what happened or has any other information is asked to call Sussex Police on 101 or email firstname.lastname@example.org quoting serial 1320 of 21/2.
You can also call the independent charity Crimestoppers anonymously on 0800 555 111.