The charity’s coracle relay race sees teams raise thousands of pounds with spectators taking to the river banks to watch and cheer on their team.
The event, which will be held on Saturday June 14 from 2pm at Pengwern Boat Club in Shrewsbury, was officially launched at Alan Ward in Shrewsbury.
Bosses from the furniture department store on Ennerdale Road joined the launch and appeal for teams after taking part in the event every year since it began.
Alan Ward was the main sponsor of the event in 2012 when more than £20,000 was raised for Shropshire Macmillan Cancer Support.
The coracle race has raised more than £125,000 for Macmillan since it was first launched in 2007.
Kathy Lesser, marketing manager at Alan Ward said: “Despite entering Macmillan’s coracle relay race every year, the Alan Ward Warriors are yet to reach the finals so we have set ourselves an extra challenge to not only take part again this year, and of course raise as much money as possible, but to also reach the finals.
“In 2012 when Alan Ward was the main sponsor, the event raised more than £20,000 for Macmillan in Shropshire which helped appoint a support manager based within the cancer unit at the Royal Shrewsbury Hospital.
“Hundreds of Shropshire families are also supported with grants to help with basic needs such as fuel bills and car parking at hospital.
“The money makes such a difference and everyone at Alan Ward is extremely proud to be part of such a fantastic event which will take place on a Saturday for the first time, so we are expecting a greater turn-out than ever before.”
The race will see 48 teams of four compete to cross the River Severn and back four times in the shortest time with many donning fancy dress to embark on the challenge.
Helen Knight, fundraising manager for Macmillan, said: “The race is a fantastic spectator sport and great fun for all of the family.
“Whilst enjoying the drama of the racing, there will also be plenty of other entertainment for all ages so why not make it a family day out?
“The funds raised will make a huge difference to those battling cancer and of course their families.”
To enter a team or for more information email coracleworldchampionships@gmail.com and you can keep up to date by visiting their Facebook page by searching for World Coracle Championships on Facebook.