Smith will bear the torch early on Saturday morning, at the start of its journey from Cardiff, the capital of Wales and home of Doctor Who, to Swansea a few miles along the coast. The day will see the torch visit the communities of Barry, Merthyr Tydfil, Rhondda and Bridgend.
Smith told the official BBC twitter feed
To carry the Torch is an honour, one I thought I'd never get, I'm very excited!The journey can be followed live via the BBC News website, starting from around 6.20am (0520 GMT). Smith will carry the torch from the Norwegian Church Arts Centre, Harbour Drive to the Senedd, National Assembly Building, Cardiff, a distance of about quarter of a mile.
The Olympic Torch featured in the 2006 Doctor Who story Fear Her, where the Tenth Doctor carried the torch on the last part of its journey towards the Olympic Stadium, as well as in the mini episode Good as Gold, shown on Blue Peter yesterday.