David Smith, who taught at Brinkburn school, South Shields, Tyne and Wear, admitted to England's General Teaching Council that on two occasions, while applying for internal promotion, he claimed to have a bachelor of education degree from the Open university.
Philip Ingram, the head, was told by another staff member about the false claims in October 2004.
Dr Ingram, who had only been in post four weeks, asked Mr Smith whether he had the qualification. Mr Smith told him he did possess the degree, but later admitted that he fabricated the qualification in an application for a temporary acting head's post, in October 2001, and again in June 2002, when he applied for assistant head. He got both posts.
He had been taking units of an Open university course but had not completed a degree, the panel heard.
Mr Smith, who had been a teacher at the 930-pupil comprehensive since 1976, was suspended and then dismissed in January 2005.
He admitted to the panel that his act amounted to unacceptable professional conduct, but stated that he had been encouraged to apply for the post, for which a first degree was desirable, by the previous headteacher and deputy head, even though they knew he did not have a degree.
In written statements, Maurice Hall, the former headteacher, and Mike Summers, the deputy head, denied encouraging falsifications.
Mr Smith said: "In hindsight I should not have lied about the first degree.
Whatever the reason, it does not justify it.
"I have suffered, in that I was sacked from a job that I loved and I was successful at."
The GTC issued Mr Smith, who has not taught since, with a reprimand, noting that he had expressed regret.