More than 50 bereaved parents and youngsters gathered at Calderglen Country Park in East Kilbride to free the insects in memory of their loved ones.
The event was organised by Forget-Me-Not Care and Counselling group which provides vital support for grieving families all over Scotland.
Linsay and David Bonar, from Blackwood, Lanark, set up the help group after they lost their son Lachlan in 2006 when he was just three days old. They raised £1100 at the Family Memor-ial Day on Sunday which will provide counselling for up to five families.
Linsay, 32, said: "It was an emotional day because the families really connected with the butterflies and felt it was a symbol of their love for their lost children.
"One couple released three butterflies because they had lost three children, another released two because they lost twins.
"One dad kissed the butterfly before letting it go.
"Another woman said she remembers seeing a butterfly on a rose bush as she left the crematorium so that was how she connected with it."
Linsay and David are also fighting for justice after their son's ashes were discarded by crematorium staff. They are helping to support hundreds of other families at the centre of the baby ashes scandal.
Last month mum Stacey Lamb, 29, from Tollcross, told her heartbreaking story to the Evening Times about how she felt robbed of her son Daniel's ashes after crematorium staff told her there were no ashes.
She has raised £1600 for Forget-Me-Not after organising a charity foot-ball match at Petershill Football Club in Glasgow's Springburn area.
Stacey's new partner Addison Restrick, 24, and her former partner, Michael Leith, 30, who was Daniel's dad, helped out.
Stacey became friends with Linsay after losing her son.