The race is held near Mountain Ash, Rhondda Cynon Taf, to celebrate legendary local runner Guto Nyth Bran and dates back almost 60 years.
With 1,500 runners registering to take part in the 2014 race, organisers say some people were unable to sign up.
A mystery runner - usually a well known sportsperson - starts the race.
Ann Crimmings, Nos Galan Committee chair, said the race route was being reviewed.
The committee plans to meet Welsh Athletics, Rhondda Cynon Taf Council and South Wales Police in the coming weeks to discuss the possibility of changing part of the route to allow more people to take part from the 2015 race onwards.
The route of the Nos Galan road race, which is held on New Year's Eve, could be changed to allow more runners to take part.