Former Scotland international Doddie Weir (centre) is pictured with Scott Hastings (left) and Gary Armstrong as he launches the trust.
The 47-year-old announced his diagnosis in June to raise awareness of the degenerative condition, pledging to devote his time to helping with research and supporting fellow sufferers.
The Doddie Weir’5 Discretionary Trust – which makes use of his rugby shirt number – will provide practical help to Weir and his family.
A foundation, My Name’5 Doddie, is also to be set up in the next few months to raise funds for research into MND and to provide grants to people living with the condition.
Weir attended the launch of the trust in Melrose in the Scottish Borders, where he began his rugby career, before Edinburgh’s pre-season friendly against Newcastle Falcons.
He said: “Since I made public my diagnosis, the response we have received from the rugby fraternity and the general public, firstly during our time in New Zealand and latterly from across the UK, has been overwhelming.
“We have been amazed at the messages of support sent to us by well-wishers – and hopefully we get around to answering those messages in time – and the kindness shown by hundreds of people.
“I would personally like to thank everyone as it has been greatly appreciated by the entire family.”
Edinburgh-born Weir won 61 caps for Scotland and was part of the squad which won the 1999 Five Nations title.
The 6ft 6ins forward was also called up for the British and Irish Lions’ 1997 tour of South Africa.
Former team-mate and British and Irish Lions captain Finlay Calder is one of the trustees.
He said: “The world rugby community, in particular, has offered enormous support and we, as trustees, believe the trust can serve as a way of giving the Weir family and other sufferers the practical help they need while raising the profile of this degenerative condition.
“We know the challenges facing anyone diagnosed with this degenerative disease.
“The trust has been set up to support Doddie and his family, and will support initiatives to help people cope with the effects of the disease.
“Hopefully we can offer practical help to make sure Doddie has the independence to live his life as fully as possible in the months and years ahead, and donations will go towards supporting these aims.”
Last week Weir teamed up with former Scotland centre Scott Hastings, an MND Scotland patron, to promote a fun run and sponsored walk to raise money for the charity MND Scotland.
Lawrence Cowan, chair of MND Scotland, said: “Since Doddie’s diagnosis, he has been an absolute inspiration.
“I know how devastating this disease is. To spend your time committed to helping others with this condition and also making sure that we raise as much money as possible to beat this disease is really incredible.”