Henry said the black, Asian and minority ethnic (BAME) community had “initiative fatigue”.
“Tony Hall’s announcement last week is something but with massive respect it’s on an old model that doesn’t work,” he added.
The BBC wants to increase BAME on-air talent to one in six people by 2017.
Speaking at a culture, media and sport select committee hearing, Henry said there had been “29 initiatives at the BBC in the last 15 years and numbers (of people from BAME backgrounds working in the industry) have gone down”.
He added: “Idris Elba and Chiwetel Ejiofor didn’t need more training. They just needed a break.”
Director general Lord Hall’s announcement last Friday also included a series of targets for staff representation off-air and several other initiatives.
In addition to a £2.1m development fund, the BBC is bringing together a group of experts, including Henry, Baroness Tanni Grey-Thompson, Asian Network presenter Nihal and Lady Benjamin, to form an Independent Diversity Action Group, chaired by Lord Hall.
“I think the group will be tough-minded,” Lord Hall said on Friday. “But it’s good to have people who are there to support you, but also say you can do better here.”
Henry was addressing the select committee during its wider review of the future of the BBC ahead of the Charter Renewal in 2016/17.
The actor and comedian wants the broadcasting industry to adopt the plan he launched at Bafta earlier this year to increase BAME representation – dubbed the Henry plan – based on the model that media watchdog Ofcom uses to classify programmes made in the nations and regions.
In response to his comments, a BBC spokesperson said: “Last week we set out far reaching plans that we believe will make a tangible difference – we will work hard to deliver them and of course reserve the option of going further if we fall short, but people should judge us on progress over the coming months and years before concluding the need for even more measures.”
Henry’s appearance at the select committee comes after the acting head of the BBC Trust, Diane Coyle, said the BBC’s flagship soap EastEnders is “almost twice” as white as the real east London.
The BBC’s audience council in England had compared the population of Walthamstow in east London with Walford, the fictional home of EastEnders.
E20 v E17
Ms Coyle said it would be “daft” for the show to be a “perfect replica” of the real world.
But she added it was “important to ask whether the BBC can do more in its popular output to provide an authentic portrayal of life in modern Britain”.
Referring to her comments that she made during a speech at the London School of Economics on Monday, Henry said: “EastEnders is the most ethnically diverse of any soap.”
The BBC said: “We agree with the trust that EastEnders has one of the most diverse casts on British television and that it would be daft to suggest that the programme needs to be a perfect replica of a particular postcode.”
Ms Coyle is in the running to become head of the BBC Trust after Lord Patten stepped down due to ill health.