Reading out loud to an English-speaker may help your pronunciation, because that person can correct your errors. When talking about reading to yourself though, typically, I'd say no. You could read a passage 50 times, and if you don't pronounce "through" like "thru," or "cough" like "coff" or place the proper accent in words (like "recommEnd" or "fInally"), reading out loud to yourself would not be all that helpful for your pronunciation. You would just be repeating and growing accustomed to those same errors.
However, there are websites that can help with this. Try http://forvo.com This way, when you read to yourself, if you come across a word that you don't know how to pronounce, you can hear from a native speaker how it should be pronounced.