The actor, 59, admitted Islamic prayer “got into his spirit” while filming in Turkish city Istanbul.
He said: “The Call to Prayer happens five times a day and for the first week it drives you crazy, and then it just gets into your spirit and it’s the most beautiful, beautiful thing.
“There are 4,000 mosques in the city. Some are just stunning and it really makes me think about becoming a Muslim.”
Liam was raised in Northern Ireland as a devout Catholic and altar boy and was named after the local priest.
But the star — whose wife Natasha Richardson died aged 45 in a skiing accident in 2009 — has spoken about challenges to his faith.
He said: “I was reared a Catholic but I think every day we ask ourselves, not consciously, what are we doing on this planet? What’s it all about?
“I’m constantly reading books on God or the absence of God and atheism.”
Liam was criticised in 2010 after claiming Narnia lion Aslan — voiced by him in the movies — is not based on Christ as CS Lewis had claimed but in fact all spiritual leaders including Mohammed.
His latest film The Grey, about an oil drilling team who crash in freezing Alaska, is released in the UK on Friday.