It is interesting to read if you are interested in history and you want to know more about Hitlers ideology. But it's mostly filled with sick ideology and insane rabble about the greatness of the aryan race and stuff like that. If you are going to read that book, before you start... just make sure you plan to don't believe anything you read.
And the writing style... well it's not a suspense-packed story if that is what you want to know.
There are commented versions for those who are historically interested. You might want to get one of those.
Its a large book that hitler wrote about his plans for the world's future.