Disease-related worry is associated with family history and perceived risk of that disease; however, the influences of general risk perceptions and tendencies to worry about diseases have been neglected in the literature. This study investigates a model of disease-specific worry which includes family history, disease-specific perceived risk, and perceived risk for and worry about other diseases. Participants completed a survey assessing these variables in relation to several heritable diseases. Structural equation modeling found that family history predicted disease-specific perceived risk but not perceived risk for other diseases. Disease-specific perceived risk predicted disease-specific worry and worry about other diseases. Perceived risk for other diseases predicted worry about other diseases and disease-specific perceived risk but not disease-specific worry. Disease-specific worry predicted worry about other diseases. This model was supported across several diseases and indicates that disease-specific and general considerations of risk influence worry about a disease and should be considered in interventions.