The Saturdays singer - who has been single since splitting from model David Gandy seven months ago - admits there are many high-profile men who have caught her eye, but those two are her favourites.
She said: ''I've heard Tom Cruise is single - but just imagine if I rang home and said, 'I'm going out with Tom Cruise.' My mum would fall off her chair! I have a weird crush on Simon Cowell too.''
However, Mollie - who is currently shooting a reality TV show with her bandmates in America - has also been doing her best to get close to John Mayer.
She told heat magazine: ''I'd like to meet someone in the US. American men do interest me, but I don't really mind where they're from, I just want a nice one.
''The first night in LA we went to Soho House and sat just a few tables away from John Mayer, and I love him.
''I really wanted to go over there. I moved seats so I could spy on him.''
Mollie is the only single member of the girl group and she admits after she split from David she initially felt ''weird'' being alone.
She said: ''It's weird, this is my first time being single.
''At the beginning, I felt like, 'Who do I call to say goodnight to? Nobody!' But you get used to it.
''It's good timing - while I'm out here, I don't have to worry about missing someone.''