In emotional scenes, people wearing football kits with Bradley's name on the back have gathered in Blackhall Colliery in County Durham, where the youngster lived.
The horse-drawn hearse carrying little Bradley was the final part of the procession, with his coffin adorned by red and white flowers made famous by his beloved Sunderland AFC.
A vigil and minute's applause are planned at Grey's Monument in Newcastle city centre at the same time as the funeral, while balloons will be released at noon at Sunderland's Stadium of Light.
Bradley Lowery inspired the nation as he bravely fought a rare form of cancer..
Speakers will broadcast the funeral service to people unable to be accommodated within the church.
David Moyes, former manager at Sunderland FC, was also among the congregation.
Bradley, who died from the childhood cancer neuroblastoma, struck a close friendship with the striker, who said the little boy would continue to inspire him.More news: China says trade with North Korea rose 10.5pc in first half
Bradley's fight against the rare cancer neuroblastoma became a national concern previous year as a massive fundraising effort aimed at getting him to the USA for for pioneering treatment.
Tributes poured in from around the world when his parents announced his death on Facebook.
Hundreds of people lined the streets to pay their respects.
The loveable Sunderland fan sadly lost his long battle with cancer last Friday, and his close friend Jermain Defoe was among those attending the funeral.
Bradley's family said they would wear football shirts in honour of his love of the sport.
Bradley led out England for the World Cup qualifier against Lithuania at Wembley in March and was a special guest at the Grand National.