Paying tribute on Instagram, the band named “their greatest loyal friend” as Con – and shared several photos of him alongside Flint, who died last month at the age of just 49.
One picture showed Con helping to lift Flint above a crowd of fans at an outdoor concert, and another showed the pair going for a run together.
The post said: “RIP Con. You always had our backs and looked after us for many years, you got us out of many sticky situations on tour, you were truly a great man, in fact you were actually Superman – the people who knew you will understand what I’m sayin.
“Above all you were the greatest loyal friend to us all man. We will truly miss you and never forget you brother. Our love goes out to Jayne and the family. The Prodigy boys x.”
His full name and age have not been released, nor have the circumstances surrounding his death.
The announcement saw fans send their condolences to the band on social media.
Dawn Doyle wrote: “Another loss for @the_prodigy. You will come back stronger and carry these loved ones with you on stage and on tour.”
Malcolm Taylor said “heaven won’t know what’s hit em with him and Keith up there”, while another fan replied: “Rest peacefully Con and tell @keithflint how gutted us music fans were across the world that we lost him x.”
Flint was found dead at his home in Essex on 4 March.
The star was famous for hits with the band including Firestarter, Breathe and Out Of Space, having emerged from the underground rave scene of the early 1990s.
Flint, who was always instantly recognisable for his spiked hair and unique style, was initially a dancer with the band before moving to sing on Firestarter and Breathe – the singles from their third album, The Fat Of The Land.
Both the singles and the album topped the charts, propelling The Prodigy into the mainstream and helping them tot up worldwide record sales currently standing at an estimated 30 million.
They had been due to tour the US in May and also play at the Glastonbury Festival in June.