The patent laws of the United States do not discriminate with respect to inventor citizenship. Any inventor, regardless of citizenship, may apply for a patent just the same as a U.S. citizen. However, U.S. patents are only effective within the United States and its territories.
There are, however, a number of points of interest to foreign applicants. A U.S. patent application must be made by the inventor and the inventor must also sign the oath or declaration (with certain exceptions), which is different from the law in many countries where this is not necessary. A patent cannot be obtained if the invention was patented first abroad before applying in the United States by the inventor or if an application was filed more than 12 months before filing in the United States (but six months are allowed in the case of a design patent).
If you are looking for assistance securing your patent in the U.S. then take a look at, where you can get a free consultation or quote from experienced patent lawyers. Feel free to private message me too!