Many veterans with posttraumatic stress disorder (PTSD) either do not seek treatment or participate in treatment only episodically. The authors conducted a retrospective cohort study using Department of Veterans Affairs (VA) administrative data to determine rates of mental health care use and to examine whether the odds of service use varied by race or ethnicity. They examined all veterans with a new diagnosis of PTSD during a one-year period. Analyses used logistic or negative binomial regression with generalized estimating equations to measure associations of race and ethnicity with mental health service use after controlling for demographic, disability, and access factors. After adjustment, veteran race, but not Hispanic ethnicity, was associated with decreases in some pharmacotherapy measures and increases in some counseling measures.