This is the first integrated biological and behavioral survey among female sex workers (FSW) in Mozambique. Using respondent-driven sampling, 400, 411 and 429 FSW were enrolled respectively in Maputo, Beira and Nampula in 2011-2012. Estimates were produced using RDSAT 7.1. HIV prevalence was 31.2%, 23.6%, and 17.8% in each location respectively. Among HIVpositive FSW, 48.1%, 79.8% and 89.6% in each city, were unaware of their serostatus. Condom use at last sex with a client was 85.8%, 73.4% and 62.8% among FSW, respectively. HIV was associated with current age, age of first sex for money, low educational level, and having had a genital ulcer in the last six months. Results suggest the urgent need to increase behavioral and structural interventions in this key population