Exotic introductions of Formosan Subterranean Termite (FST) to the United States from Asia have had significant economic consequences. Multiple introductions through marine transport have been proposed, but identification of these routes has yet to reveal more than one lineage in the continental U.S. DNA sequencing of a 640-bp cytochrome oxidase II (COII) mitochondrial DNA (mtDNA) marker to 60 disjunct populations, revealed two independent lineages spanning the continental U.S., Hawaii, Japan, and China. Limited genetic variation was observed with this marker. Group I constitutes a largely Asian clade, while Group II is comprised of both Asian and southern U.S. populations. This is the first study which has documented 2 distinct lineages to continental United States and Hawaii.