The 99-year-old, who has raised over £23 million ($28.7m) for the NHS, joined in with singing 'You'll Never Walk Alone' along with Michael Ball and the NHS Voices for Care Choir.
All proceeds from the single will go to Tom's walk fund and be donated to NHS Charities Together.
Taking to Twitter, one person wrote: "Have to admit this made me cry... Well done Captain Tom, Michael Ball and the Choir."
Another added: "Phew, this should come with a health warning and a box of hankies. Well done to everyone involved in this and deep respect for you all."
A third commented: "Well I'm glad I'm not wearing mascara. Glad no one can see me weeping (again!). What a wonderful thing to see and hear. So pleased it's No 1 and not surprised. Well done and thank you all involved but especially Captain Tom and Michael Ball."
Captain Tom was on a mission to complete 100 laps of his garden to raise money for the NHS during the coronavirus pandemic. He was planning on doing laps of the 25m-long space outside his home in Marston, Moretaine, Bedfordshire.
Originally, he aimed to raise £1,000 ($1,250) by doing 100 laps before he turns 100 at the end of the month, as a way of saying thank you to the NHS for all the help he's received over the years.
However, at the time of writing, his JustGiving page stands at £23.4m.
Speaking to BBC News after completing the feat, he said: "This is for everyone for who is finding the current circumstances difficult, and it is difficult. Everyone who is staying indoors, you're all being very very good."
He added: "You've all got to remember that we will get through it in the end. It will all be right. It might take time, but it will all be OK. The sun will shine on you again and the clouds will go away."
Tom was born and raised in Keighley, Yorkshire, and went on to be enlisted in the eighth battalion of the Duke of Wellington's Regiment (8 DWR) at the beginning of the war. In 1940 he was selected for Officer training, and was later posted to 9 DWR in India, later serving and fighting on the Arakan.
To continue helping Tom raise money, visit: www.justgiving.com/fundraising/tomswalkforthenhs.