The model was set to join the reality show along with Duncan James, which sees celebrities help couples organise their nuptials.
However, she has left the production after recently getting married herself for a third time, according to The Sun.
An insider said: "Bosses really wanted Katie to do Celebrity Wedding Planner but she has now told them she can't.
"The talk is that she just can't face organising another wedding after getting hitched for the third time herself."
Blue singer James has also quit the show, the tabloid claims.
Price's spokesperson confirmed that she will not be part of the show, but added that it was due to her busy schedule.
They said: "Katie was not confirmed for Celebrity Wedding Planner because the dates wouldn't work for her diary."
Jedward, Amy Childs, Martin Kemp and MC Harvey helped arrange weddings in the previous series. Channel 5 will announce the new lineup soon.
Price married former stripper Kieran Hayler earlier this year after dating for around six weeks.
She confirmed earlier this week that she is expecting her fourth child.
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