If you are an eligible voter and have never lived in the U.S., you should use your U.S. citizen parent's current or last U.S. residence address.
We recommend that you check that you are registering in one of the states that allow U.S. citizens born overseas (and who have never lived in the U.S.) to vote, as well as to verify the specific rules of that state. You can find this information for each state in the question “I’m an American citizen born overseas – can I vote?”, which can be found in this section of the FAQ.
Note that in order to qualify, your parent must also be eligible to vote. If both of your parents are U.S. citizens and have different last U.S. residence address/es or current address/es, (or, if military, legal residence), you may choose either address.