Leigh Smithson, formerly of Brent council's key stage 4 pupil referral unit in Kingsbury, London, was found guilty of unacceptable professional conduct by England's General Teaching Council.
PC Graham Hammersley, who interviewed him prior to his conviction for assault causing bodily harm in November 2003, told a GTC professional conduct committee: "He scares me. I am convinced he will kill one day."
Mr Smithson was given a six-month prison sentence after assaulting his former fiancee.
She told the hearing that she had forgiven him and pleaded with the council not to ban him from teaching. "For him to be deprived of his teacher status is wrong," she said in a statement.
Mr Smithson, who now lives in Prague in the Czech Republic and teaches English to business people, also asked to be spared.
In a written statement, he apologised for his actions and submitted medical evidence which suggested it was possible that he behaved totally out of character because he was taking an anti-depressant.
He said: "I accept full responsibility for what I did and don't want you to think I'm making excuses."
Mr Smithson said he was trying to get his life back together and intended to return to teaching: "The whole thing has taken a massive toll on me. I dearly want to return to my passion, which is teaching."
But the GTC committee, meeting in Birmingham this week, ruled that he had brought the profession into disrepute.
It issued a two-year prohibition order, which offers Mr Smithson the opportunity to return to teaching by reapplying to the GTC for restoration of his registration in 2007.
The council heard that he attacked his former partner after a night out drinking in October 2003. The incident happened while he was employed at the pupil referral unit for children aged 13 to 16 who had been permanently excluded from mainstream schools.
The council heard that Mr Smithson jumped on his fiancee while she slept and inserted his fingers into her mouth. During the struggle he twisted her jaw, bit her forearm and broke her forefinger.
The victim's 31-year-old son ran upstairs from where he was sleeping after hearing her cries for help, and restrained Mr Smithson while his mother dialled 999.
But Mr Smithson managed to break free and attacked the woman and tried to push her off a 12ft balcony. She escaped his grasp and pushed him down a flight of stairs.
Police arrived to find Mr Smithson threatening to jump off the balcony. He fell and was taken to hospital.
The woman told police: "I feel as though I would have died on that night if my son had not come to my rescue."
PC Hammersley told the hearing that during his interview with Mr Smithson, he said he "may have been rough with her", but only remembered shaking her.
Mr Smithson was later convicted of witness intimidation after making several anonymous phone calls to his victim. He denied the charge until police showed him CCTV footage of him making the calls.
PC Hammersley said: "Only when you could catch him out would he admit to something. He's a very clever man."