Bosses at Ormiston Maritime Academy say 'immediate action' was taken following allegations that a sexually-explicit photo of a woman was sent between staff using the school's network system.
A spokesman for Ormiston Academies Trust said: "As soon as we were made aware of allegations of inappropriate conduct we took immediate action and suspended the members of staff involved, without prejudice, while a full investigation takes place.
"As we are now in a formal process it would be entirely inappropriate to comment further, except to say that we remain focused on providing the best possible care and education for the pupils of Ormiston Maritime Academy."
The incident came as the school came under criticism from Ofsted inspectors who branded the school "inadequate".
It was the academy's first inspection since converting from Hereford School in November 2011.
The head teacher Elaine Davies defended the school and said there was now "a better calibre of staff", remarks which themselves had prompted a furious backlash from former staff and pupils.
She said there had been measurable progress since the December report.
Ofsted's report on a follow-up monitoring visit was published yesterday and described the school's action plan as "fit for purpose".
