G4S have vast experience in managing football, cricket, rubgy and other events including live concerts.
They will also play a major part in security issues at this years London Olympics.
Their managing Director Eric Alexander said to the clubs website: 'We are delighted at our new partnership with Rotherham and are looking forward to developing our relationship and supporting the transition to their new stadium.
"It is great to be expanding our footprint in this part of the country and we are looking forward to using our extensive experience to provide a seamless security solution whilst expanding our football credentials."