The screen veteran, who played the seventh incarnation of the Time Lord in the 1980s, is backing Barnardo's Great Winter Stock Appeal, a drive which urges Brits to clear out their winter closets and donate warm clothes.
MCCoy has handed some of his own items over for auction, including his iconic colourful scarves and tank tops from his Doctor Who days, as well as items collected during his time playing wizard Radagast the Brown in The Hobbit franchise.
He says, "I was happy to take the time to get involved in this very important appeal for Barnardo's. They urgently need donations of pre-loved winter coats, woollies and accessories to help their stores build the stock they need to sell this winter. Now that spring is finally here, it's the perfect time to clear out winter items you no longer need.
"I had a good winter clothes clear-out myself for the appeal and if I can encourage people to join me, we can all make a difference to the lives of vulnerable children."
The auction will run on eBay.com until 21 April (14).