John Dunford, general secretary of the Secondary Heads Association, made the remarks at the Liberal Democrat conference in Blackpool, where delegates voted to campaign to close the funding gap between schools and colleges.
Mr Dunford told a fringe meeting that secondary heads were sympathetic towards college principals and could not understand why they did not have many of the same benefits, such as the option of applying for specialist status which gives schools around pound;600,000 extra over four years.
He said: "There is a wide recognition in the school sector that colleges are not as well-funded as schools.
"There is no reason, for instance, why sixth-form colleges cannot apply for specialist status. There is a big injustice here and we need to repair it."
As FE Focus went to press, SHA's council was expected to vote in favour of changing its name to the Association for School and College Leaders, or ASCoL. It hopes to attract more members from the further education sector.
Delegates at the Lib Dem conference voted unanimously in favour of a motion criticising the funding gap between schools and colleges, estimated at between 10 to 15 per cent, and calling for it to be closed over the lifetime of this Parliament.
Baroness Sharp of Guildford, who proposed the motion, said: "It is fundamentally unfair on the college sector which often provides a second chance for students who have been failed by schools.
"They should not have to compete with their arms tied behind their back in this way."
The only voice of dissent was that of Laura Murphy, a delegate from Tunbridge Wells, who said that the proposals did not go far enough to address the underfunding of FE colleges.
She said: "This motion is too simplistic. It's like a sticking plaster on a suppurating wound," she said.
Ed Davey, Lib Dem education spokesman, admitted he had only become aware of the significance of further education colleges and their work with some of the country's most deprived teenagers since taking on the post in May.
He urged party activists to raise awareness of the funding gap but to take care their campaigns did not damage the intakes of their local colleges by drawing parents' attentions to their financial difficulties.
Natfhe on funding gap, Letters 4