The reality TV star, who is suffering from terminal cancer, attended the service at the Royal Marsden Hospital in west London where she is being treated in the final stages of her illness.
Goody, 27, had hoped to be christened in church but was too ill to leave the hospital.
Her publicist Max Clifford said she had been "very pale and fragile" during the service and was in a wheelchair dressed in a hospital gown and assisted by nurses and christened alongside her sons Bobby, five, and Freddy, four.
Clifford said it was the last thing that Goody would do publicly and that he thought she was "saying a final goodbye to some people". He added that she had a "smile and a kiss for everyone who was there".
Goody's husband, Jack Tweed, mother Jackiey Budden and her sons' father, Jeff Brazier, were among about 20 close friends and relatives at the private service yesterday.
The mother of two has only weeks to live after her cervical cancer has spread to her liver, groin and bowel.
Speaking afterwards, Clifford said Goody's ill health did not stop her enjoying the service.
He said: "She finds it very hard to stay awake for more than a few minutes but she stayed awake for the 20 minutes of the service.
"It was a very positive atmosphere. After each of the boys were christened everyone clapped, and after Jade was christened everyone clapped again.
"It was a very simple service. There were prayers and blessings and a few short readings."
He added that the reality TV star was saying goodbye to some people for the final time following the ceremony and it was unlikely she would leave the hospital.
Clifford said: "Speaking for myself, I'm no medical expert, but I doubt she will leave. This is the best place for her. Last week she was in a great deal of pain and nobody wants her to be like that again.
"Sometimes, when people are very, very ill, they need to focus on something and it keeps them going."
He added that it was unclear how long Goody would survive, saying: "It's not something you can predict. Everyone is different. The most important thing is the quality of life she has left. I hope the boys get a chance to see her again. The two things she said to me were she wanted to get married and have the christening, and she has done them both and done them her own way, with style."
Clifford said Goody was in no doubt that she wanted photographs to be taken of the event and published.
He said: "Obviously the money from this will go to her boys and that is what she's always wanted."
The service was carried out by hospital chaplain Chris Lee and Corinne Brixton, vicar of St John's Church in Buckhurst Hill, Essex, near Goody's home.
Her grandfather, John Caddock, said the service had been beautiful. He added: "It was very special."
Photographs taken of the service are to be published in OK! magazine as part of a 700,000 deal to ensure her sons' financial future.
Tweed, 21, is awaiting sentence after he was found guilty of attacking a taxi driver. After the christening, the family went to a nearby pub and then to a London restaurant. After leaving the restaurant in Knightsbridge, Tweed had to be restrained by one of his friends after getting into an argument at a London Underground station.