Lorraine Kelly, McFly star Tom Fletcher and wife Giovanna, and Gaby Roslin were among the attendees at St Mary’s Church in Barnes on Wednesday afternoon.
Dame Deborah – the podcast host and mother-of-two, who became known as Bowelbabe, her social media handle – died last month aged 40 after being diagnosed with bowel cancer in 2016.
The service saw husband Sebastien deliver a eulogy while their children Hugo and Eloise both read poems.
Family friend and classically trained jazz singer Natalie Rushdie, who is married to novelist Salman Rushdie’s son Zafar, sang Tell Me It’s Not True from the musical Blood Brothers.
Cellist Charles Watt played music from Gabriel Faure, while family friend Sarah Mountford read an extract from Ecclesiastes.
After the service, the family left the church with bowed heads for a private wake, while Dame Deborah’s coffin was carried away by car.
The Rev David Cooke stood at the gates to wish the mourners farewell.
On Wednesday morning, Dame Deborah’s coffin had arrived in a vintage Rolls-Royce hearse with more than a dozen members of family walking in procession behind.
Her husband and son were among those who carried the wicker coffin, adorned with the rose that bears her name, into St Mary’s Church in Barnes on Wednesday afternoon.
Earlier this year, Dame Deborah had a rose named in her honour, which went on display at the RHS Chelsea Flower Show.
Ahead of the service, family members also carried a wreath of white flowers into the church.
An attached note said: “Deborah, thank you to our extraordinary friend. You together with Seb, Eloise and Hugo are such an important part of our family, we will love and miss you forever.”
The church bells chimed at 12:30pm ahead of the service, which began at 1pm.
Dame Deborah, a former deputy headteacher, was diagnosed with bowel cancer in 2016 and subsequently kept her nearly one million Instagram followers up to date with her treatments.
Her candid posts about her progress and diagnosis, including videos of her dancing her way through treatment, won praise from the public and media alike.
Dame Deborah revealed in early May she had stopped active treatment and was seeing out her final days at her parents’ home in Woking, Surrey.
She received end-of-life care with her husband, Sebastien, and their two children, 14-year-old Hugo and 12-year-old Eloise, by her side.
In her final months, the presenter of the BBC podcast You, Me And The Big C raised almost £7 million for cancer research, with the amount climbing further following her death.
She was made a dame for her “tireless” work improving awareness of the disease, with the honour conferred by the Duke of Cambridge, who joined her family for afternoon tea and champagne at home.
Her death was announced on June 28 with a message saying she had died peacefully, surrounded by her family.
William and Kate, charities, celebrities and many whose lives have been affected by cancer shared tributes.