Inadequate knowledge of family health history (FHH) continues to be a major obstacle limiting its usefulness in public health and clinical practice; strategies to facilitate FHH dissemination are needed. Data (N = 1,334) were obtained through waiting-room surveys completed by a diverse sample of patients attending three community health centers. Perceptions about the importance of genetic information (β = 0.13, p < 0.001; β = 0.11, p < 0.001) and higher genetic self-efficacy (β = 0.14, p < 0.001; β = 0.23, p < 0.001) were significantly associated with higher levels of perceived familiarity with and importance of FHH, respectively. Furthermore, beliefs about genetic causation of illnesses (β = 0.12, p < 0.001) and a wider reach of health communication within one's family (β = 0.15, p < 0.001) were associated with higher levels of perceived familiarity with one's FHH. Participants in the oldest group (>50 years) reported higher familiarity than those in the youngest (18-25 years). Those with higher familiarity were significantly less likely to answer "don't know" when reporting diabetes and heart disease diagnoses among immediate (OR = 0.35 and OR = 0.29, respectively) and extended (OR = 0.50 and OR = 0.46, respectively) family members. Having a wider health communication reach within a family may be beneficial in increasing familiarity with FHH; however, the reported levels of communication reach were limited among most participants. Women, older-generation family members, and those who believe in the importance of genetics in health or feel confident about using genetic information may be particularly important as targets of public health interventions to facilitate FHH dissemination within families.