John Barnard, 66, is a fellow at the Royal College of Organists and has been sentenced to four months in prison with an 18 month suspended sentence.
Mr Barnard taught at an £18,000 a year all-girls school in London, Godolphin and Latymer school.
Sitting in Harrow Crown Court Judge Jeremy Barklem said: "You are a cultured, educated, highly intelligent man, respected and loved by many... but also tortured by a publically-repressed sexuality and an interest in images of young men that's never been expressed physically."
John Barnard, from Harrow, has admitted making and possessing indecent photographs. According to the Evening Standard most of the images depicted boys aged between 14 and 16.
Mr Barnard was also made subject to a five-year Sexual Harm Prevention Order and must sign the sex offenders' register for seven years.
