Speaking after the first conference for black Anglicans, Dr Sentamu, chairman of the church's committee on black Anglican concerns, said: 'You cannot say the church is less racist, but the church is more willing to accept that in the past there has been racism, and is determined to root it out of all its structures.'
A statement issued by the delegates at the close of the conference described the weekend as a 'trumpet call' and called for all discrimination in the church whether 'knowing or ignorant' to cease.
The delegates also urged that inequalities in society should be addressed, particularly in jobs, housing, health or education.
But Dr Sentamu, who called for urgent action when the committee's report on racism, Seeds of Hope, was published three years ago, said the church should put its own house in order first.
'How can the church talk about justice, if we don't show justice?' he said. 'No one will listen to us.'
However, he said important first steps had been made towards change. 'I never dreamt this conference would ever happen, but the church is now listening and willing to co-operate.'
At present, 4.5 per cent of Church of England worshippers are black, but less than 3 per cent have put their names on the electoral roll of the church they attend - meaning they are underrepresented on the councils and synods which make the key decisions.
In one diocese although 14 per cent of people attending church were black, less than 1 per cent held positions of responsibility.
The conference culminated in a service of celebration at York Minster, where the sermon was preached by the Bishop of Croydon, the Rt Rev Wilfred Wood, who was the first black bishop in the Church of England.