Addington long barrow is a badly damaged Neolithic chambered long barrow near Addington in the English county of Kent. It is one of a group of monuments known as the Medway megaliths.

It is rectangular long barrow measures 61m in length and varies from 14m to 11m in width as it narrows. It is orientated north east.- south west. The edge of the barrow is marked by a kerb and the remains of the chamber may be indicated by a number of fallen stones at the north eastern end.

A road runs through the middle of the barrow and when it was expanded in 1827, two stones from the kerb were removed and placed in woodland south of the monument. In 1845, LB Larking, a local parson dug into the barrow, finding pieces of 'rough pottery'

In 1981, archaeologists surveyed the site identifying 25 original stones on all four sides of the structure, forming a peristalith. A slight depression surrounding the mound may indicate the presence of a surrounding ditch.