Adriana Nelson, née Pirtea (born January 31, 1980) is a Romanian American long-distance runner who competes in distances up to the marathon. She competed at the 2005 IAAF World Half Marathon Championships and 2006 IAAF World Road Running Championships for Romania, then at the 2012 IAAF World Half Marathon Championships for the United States. At national level, she won six long-distance track titles at the Romanian Athletics Championships and was the 2013 winner at the USA Half Marathon Championships.