The X Factor judge said Brits miss out on uplifting sermons like Bishop Michael Curry's at Prince Harry and Meghan Markle's wedding.
Speaking to the Express, Osbourne, 65, said: "The churches are empty because the services are boring.
"They need more of the emotion we saw from the Bishop [Michael], who was animated and fabulous."
Bishop Michael's sermon generated widespread media attention with many Christians and non-Christians commending its charismatic tone.
However, a poll by Christian Think Tank Theos found the wedding sermon didn't leave a lasting impression on Brits, despite the initial praise it received.
*Only 16% of respondents to their survey sid they would be more likely to go to church if the preaching was similar to Bishop Curry's and only 12% thought the sermon improved their understanding of Christianity.*
But Osbourne, daughter of Jewish music promoter Don Arden, said most churches in the UK are "too straight" and credited her move to the US as allowing her to "sneak through the British way of life and to become so much more emotional".
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