People applauded and threw flowers as the cortege passed slowly through Heckmondwike and Batley earlier.
The mother of two young children died on 16 June after being shot and stabbed outside a library in Birstall.
Amongst the mourners were school children, who held white roses as the cortege passed by.
People also left floral tributes and placed posters and placards along the route pledging to "Love Like Jo".
Live updates and tributes on Jo Cox's funeral
The mother of two young children died on 16 June after she was attacked outside the library in the village of Birstall.
Her killing provoked a wave of shock worldwide and a memorial fund set up by Jo's husband and friends has raised nearly Â£1.5m for organisations she supported.
Ahead of the funeral, Jo's family said: "Knowing that so many people share both our grief and our determination to take forward Jo's legacy is a source of great strength at what otherwise feels like a very bleak time."
Hundreds of people have paid their respects to Labour MP Jo Cox's Batley and Spen constituency ahead of a private family funeral service.