The presenter posted a photo of herself holding her beloved pet dog Maggie in what appeared to be the garden at her family's home in Surrey.
Maggie licked her lips, happy in Ruth's arms, and the star smiled as she wore large sunglasses and a blue and pink Alzheimer's Society T-shirt.
In the caption for the photo, Ruth expressed her gratitude to everyone who was walking at the weekend to raise money for the charity.
WATCH: Ruth Langsford thrills fans with glimpse of super-organised home
She wrote: "To everyone doing their @alzheimerssoc Memory Walk 2020 today... Sorry we can’t be together but from me & Maggie thank you all for still walking.
"If you haven’t already signed up it’s not too late, Memorywalk.org.uk. Remembering all our loved ones today [heart emoji]."
The 60-year-old lost her dad Dennis, with whom she was very close, to Alzheimer's back in 2012.
She previously spoke about him while appearing as a panellist on Loose Women, breaking down in tears three years ago when she talked about his dementia.
Ruth shared the message alongside a sweet photo with dog Maggie
She said: "I was grieving and losing my dad but my mum was losing the love of her life, the man she married and had children with.
"They had years and years of memories. You don't often hear people talking about that side of it.
"When my dad went into care, my mum was so distraught... You do hope, but you know they probably won't get better."
On Sunday, the star's friends and followers were quick to share their support for the mum-of-one, including Amanda Holden, who posted a heart in response.
Another commented: "Well done Ruth, next year everyone will be together, hopefully xxx," and a third wrote: "Well done. I’m also doing mine today. Today is such an important day."
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