how easy is it to get a job in Malta only speaking English?

Depends on the industry and the position. What kind of job do you have in mind?

it can be done , my partner has had a few jobs since he got here , he worked as a stores person , a part-time it person and a kitchen hand  , he doesnt speak any language other than english and for the last two months has been working full time as an it manager .
But yeah depends what your looking to do

not just what she is looking for , but also what are her set of skill's
labor jobs - waiter, kitchen help... low paid jobs - sure, no problem if you don't speak maltese, just the pay is ....

I personally work in an audit firm with zero knowledge of Maltese. I don't think it difficult to find a job without speaking Maltese. However, in my experience, I find it difficult to actually "fit in" as Maltese speakers will speak Maltese between themselves even though you are just next to them, in the same working space.
Good luck.

Thank you for all your replies, all that you are saying is good to know and I am hopeful of the future ahead

hi.....I would like to live and work in Malta but I speak only English.....I have experience  in sales,receptionist etc.and how can I find legally job vacancies in Malta.....are the job agencies .....thanks....

Learning a little maltese would be worth the effort to fit in... its difficult to learn but so worth it  - give it a go.... its fun too - learn to laugh together with it.