There is no historical evidence outside of scripture. As elsewhere mentioned, the earliest biblical figure who name has been found outside of the Bible is King David (Assyrian texts mentioned so-and-so of the house of David).

Edit: The text if you want to look it up is the Tel Dan Stele

While it's true that there is very little historical evidence to prove that Moses existed, it is interesting to note that 'Moses' is actually an Egyptian name. If the Israelites were inventing a Jewish hero, why would they give him a name which belonged to their former pagan slave masters? That's probably the best testament we have to his existence.