Doctors from 141 nations have registered to practice in the UK during the competition, figures from the General Medical Council suggest.
The GMC, which oversees all doctor registrations, said that 849 foreign doctors had applied for temporary registrations, and it was processing a further 29 applications.
The doctors are registered temporarily and can only treat non-UK nationals for the duration of the Games.
GMC chief executive Niall Dickson said: “Doctors play a vital role at all levels in all sports and of course at the highest level their contribution is critical.
“London 2012 is a great national occasion and we are proud to have played our small part by enabling overseas doctors to come here and support their Olympic athletes during the Games.”
Eighteen doctors will be supporting Team GB’s 542 sports men and women ,while the French team has registered 58 doctors, the highest number for any country, to support their 333 athletes.
The GMC has rejected 40 applications, including one by Mexico for a vet and another by Venezuela for a masseuse, as neither need to be registered with the GMC.
The total number of nations competing - 203 - means that arond 62 nations are not bringing any medical staff to support their Olympic and Paralympic teams.