OBJECTIVES: To determine the association of socioeconomic position indicators with mortality, without and with adjustment for modifiable risk factors. METHODS: We examined the relationships of 2 area-based indices and educational level with mortality among 9338 people (including 8094 younger than 70 years at baseline) of the Australian Diabetes Obesity and Lifestyle (AusDiab) from 1999-2000 until November 30, 2012. RESULTS: Age- and gender-adjusted premature mortality (death before age 70 years) was more likely among those living in the most disadvantaged areas versus least disadvantaged (hazard ratio [HR] = 1.48; 95% confidence interval [CI] = 1.08, 2.01), living in inner regional versus major urban areas (HR = 1.36; 95% CI = 1.07, 1.73), or having the lowest educational level versus the highest (HR = 1.64; 95% CI = 1.17, 2.30). The contribution of modifiable risk factors (smoking status, diet quality, physical activity, stress, cardiovascular risk factors) in the relationship between 1 area-based index or educational level and mortality was more apparent as age of death decreased. CONCLUSIONS: The relation of area-based socioeconomic position to premature mortality is partly mediated by behavioral and cardiovascular risk factors. Such results could influence public health policies.