The Barnardo’s ReachOut centre, off Moorgate Road, was given the cash from the Home Office’s Trusted Relationship Fund.
Crime minister Victoria Atkins visited ReachOut yesterday (Tuesday) to announce more than £12 million to be split between 11 areas nationally.
She said she chose Rotherham for the launch to celebrate the success of the centre, which was set up in 2016 after the town's CSE scandal.
A report by Professor Alexis Jay in 2015 found at least 1,400 children from Rotherham were sexually exploited by gangs of predominantly Pakistani heritage between 1997 and 2013 while those in authority failed to act.
Earlier this year, the National Crime Agency, which is investigating historic cases of abuse in a bid to find offenders, said the number of victims had risen to 1,510.
Ms Atkins said: “It is awful to think so many children have to tackle life without a strong adult figure they can confide in and that this may leave them vulnerable for predatorial criminals.
“The Government is committed to helping young people and this fund is just one way we are intervening early.
“I chose to launch this in Rotherham because it's a very important place and one which I take a great deal of interest in, in terms of my responsibilities, and in terms of CSE.”
Barnardo’s said the money, which will be given over the next four years, would help widen the scope of support from sexual to other forms of child exploitation, such as gangs.
Charity chief executive Javed Khan said: “We are delighted to be working in close partnership with Rotherham Borough Council to deliver the Trusted Relationship Fund to children and young people.
“Barnardo’s is known and trusted across Rotherham and is incredibly proud to have supported vulnerable children and families affected by child sexual exploitation there since 2013.
“This new funding will allow us to build on what we have achieved and support more young people.”
The fund was announced in February after a review stressed the importance of a trusted adult in children’s lives.