Shopkeeper Alice Wheeldon was found guilty of a poison plot against David Lloyd George in 1917.
Since her death in 1919, a campaign has emerged to clear her name.
Her former home at 12 Pear Tree Road, Normanton, is being marked with a plaque in a ceremony organised by Derby Civic Society and the city council.
Keith Venables, from the Derby People's History group, which campaigned for justice for the family, said: "It's wonderful to celebrate the contribution of Alice Wheeldon and her family. Their name was vilified."
Mrs Wheeldon, a mother of four, supported the suffragette movement and was a conscientious objector to World War I.
Mr Venables believes she was framed by the authorities who were anxious about opposition to the war.
The radical women who fought for the vote
The family claimed an MI5 agent, posing as an objector, embroiled Mrs Wheeldon in a plot to poison dogs guarding prisoners against the war.
However, the family were accused of plotting to murder the prime minister by shooting him with poisoned darts.
On 31 January 1917, Mrs Wheeldon, her daughters Hetty and Winnie and son-in-law Alfred Mason were arrested and charged.
Mrs Wheeldon was sentenced to 10 years, Alfred seven years and Winnie five years. Hetty was acquitted.
Mrs Wheeldon went on a hunger strike and was released after nine months but died shortly afterwards.
Historian Dr Nicholas Hiley, who researched the family's story, said: "The whole thing was a travesty.
"The truth about Alice Wheeldon deserves to be publicised and the blue plaque is the beginning of that. The Wheeldons should be honoured and remembered for the stand they took during the war."
Mrs Wheeldon's descendents moved to Australia, but her great-granddaughters, Deirdre and Chloe Mason, are visiting Derby for the ceremony.
They hope to prepare a miscarriage of justice application to go before the Criminal Cases Review Commission.
A Derby suffragette, who was convicted of attempting to murder a prime minister, is being honoured with a blue plaque.