Premastication (i.e., chewing foods or medicines before feeding to a child) was reported recently as a route of human immunodeficiency (HIV) transmission through blood in saliva and has been associated with transmission of other pathogens. Approximately 14% of caregivers in the United States report premastication; however, the frequency of this behavior among HIV-infected caregivers is unknown. To assess the prevalence of premastication among caregivers of children being treated in pediatric HIV clinics, which include perinatally HIV-exposed children (i.e., HIV-uninfected and HIV-infected children born to an HIV-infected mother), CDC conducted a cross-sectional survey at nine such clinics in the United States during December 2009-February 2010. This report describes the results of that survey, which indicated that among primary caregivers of children aged≥6 months, 48 (31%) of 154 reported the children received premasticated food from themselves or someone else. Approximately 37% of black caregivers reported premastication, compared with 20% of non-black caregivers (prevalence ratio [PR]=1.8). Premastication decreased with caregiver age and was used to feed children aged 136 months. Public health officials and health-care providers should educate the public about the risk for disease transmission via premastication and advise HIV-infected caregivers against the practice.