Peter Russell, 59, was shot with the 50,000-volt stun guns during a struggle with SIX cops in front of his distressed wife.
The former farm worker tried to rip out the Taser darts before officers reportedly tied up his arms and legs.
Humberside Police said the controversial electronic weapon was used because Mr Russell refused to be sectioned under the Mental Health Act.
His wife Diane, 50, slammed cops for using Tasers on her husband and is threatening to launch a formal complaint.
She said her husband was left traumatised by the incident in Epworth, Lincs.
The mum of two added: “There was no need to use the Taser.
"If he was a wife beater or an armed robber then I could understand it but this is someone who will stop his tractor when ploughing a field and move a nest of mice to the side."
Mrs Russell, who spoke out to prevent other families from going through the same ordeal, said her husband became agitated when police came to assist doctors with his transfer to hospital.
She told The Daily Mail: "He was fighting them off because he didn't want to go. He was petrified and scared. I remember saying, 'It's the Alzheimer's.’
"He had not been armed and wasn't about to kill himself. They should not have Tasered him."
The Alzheimer’s Society charity also criticised the police, saying using the weapon on a dementia sufferer was “very alarming” and must have been “particularly distressing”.
Spokeswoman Sarah Moody said: “The Alzheimer’s Society is very alarmed at the use of a Taser gun on a vulnerable person with early onset dementia, which must have been a particularly distressing experience for the gentleman concerned.
“People with dementia can sometimes exhibit extreme agitation, which can be difficult to understand and cope with for those who encounter it.
“This unfortunate incident illustrates a lack of understanding in society of dementia and the best way to support and help people who are affected by this devastating condition.”
Chief Superintendent David Hilditch, of Humberside Police, described the incident as “very sad”.
He said: “Our police officers and PCSOs have a variety of difficult situations to deal with on a day-to-day basis and are trained to tackle a variety of different situations.
“It’s very sad that this gentleman had to be restrained through the use of a Taser but the officers were faced with a significant level of violence.
“It is to their credit that they successfully restrained the 59-year-old man without injury to himself and took him to a place of safety to be treated.”
Two officers suffered minor injuries in the incident on March 6.