Jessica Breeze, 20, denied murdering Colin Brady, 49, at the family home in Keith Road, Middlesbrough, in June.
Miss Breeze told Teesside Crown Court her father had frequently injured her in regular bouts of violence.
He had punched and threatened to kill both Miss Breeze and her mother before he was knifed in his back.
In evidence, nursery worker Miss Breeze had described her father as “controlling” and recalled he would “kick off” and “smash the place up” if she returned home late.
Asked by her barrister, Simon Russell Flint QC, if she ever reported her father’s violent outbursts she replied: “No. I was scared. I thought it was pointless.”
The prosecution had claimed an argument broke out after Miss Breeze’s parents discovered she had been secretly seeing her boyfriend when she said she had been at work.
During the row Mr Brady slapped or punched his then 19-year-old daughter several times, before her mother intervened, the court heard.
“He was punching me in the face with his fists,” Miss Breeze told the jury. “He said he was going to kill us.”
She was one digit away from dialling 999 when he demanded she hand over her phone, the court heard.
The court was told she had “no memory of picking up the knife”.
The prosecution claimed she stabbed her father in the back as he was leaving the house.
He was taken to James Cook University Hospital with an 18cm-deep wound to his left lung, the jury heard, but could not be saved.
Outside court, Miss Breeze’s solicitor, Sean Grainger, said in a statement: “The jury accepted she was acting in lawful self-defence of herself and her mother when under a sustained and violent attack by her father.
“Further, whilst Jessica was brought up in a highly toxic home environment where she and her mother were regularly subject to extreme physical and emotional abuse by her father, Jessica wishes to make it clear she loved her father, she still does and wishes he was still here.
“She now wishes to rebuild her life, get back to work and move on from the seven-month ordeal she has endured since her arrest.”
Following the acquittal, a CPS spokesperson said: “While there was evidence of a sometimes violent relationship between the victim, Colin Brady, and the defendant, Jessica Breeze, the circumstances of his death made a charge of murder wholly appropriate in this case.
“Regardless of the alleged provocation for the attack, the victim was attacked in the back as he walked away from the defendant.
“He was stabbed with such force that it passed from his back through his entire left lung and into his chest. Despite claims of self-defence by the defendant, the evidence was such that there was a case to answer.”