Objective: This study examines the factor structure of the Brief Symptom Inventory-18 (BSI-18; Derogatis, 2001) in a hard-to-reach population of mainly undocumented migrant Latino day laborers. While, the BSI-18 has been found to be a valid and reliable measure of psychological distress, cross-cultural assessments in sub-groups of Latinos are scarce with this being the first study to examine the factor structure of the Spanish version of the BSI-18 with this population. Methods: A series of principal axis exploratory factor analytic procedures examining one to three-factor models were performed with a street recruited sample of 150 Latino migrant day laborers. Results: A one-factor model emerged and four items were dropped due to low factor loadings. The internal consistency coefficients for the 14-item BSI was a = 0.87. Conclusions: Findings suggest that the revised BSI-18 appears to measure a single dimension of general somatic-psychological distress in this sample of Latinos.