<p><b>OBJECTIVE: </b>The objective of this study was to evaluate cross-sectional associations of sodium and potassium with BMI, waist circumference (WC), and body fat and to determine whether the nativity and/or duration of United States (US) residence modified these associations.</p><p><b>METHODS: </b>Sodium and potassium were derived from 24-hour diet recalls from 16,156 US participants of the 2008 to 2011 Hispanic Community Health Study/Study of Latinos (HCHS/SOL) and from 24-hour urine in 447 HCHS/SOL participants. BMI, WC, and body fat were measured.</p><p><b>RESULTS: </b>Dietary sodium that was 500 mg/d higher was cross-sectionally associated with a 0.07-kg/m higher BMI (P < 0.05) and a 0.18-cm larger WC (P = 0.04). Dietary potassium that was 500 mg/d higher was only associated with lower BMI and smaller WC among those who were foreign-born with 10 + years in the US (-0.13 kg/m , P < 0.01 and -0.36 cm, P = 0.01, respectively) and among those who were US-born (-0.62 kg/m , P < 0.01 and -1.42 cm, P < 0.01, respectively). Urinary sodium that was 500 mg/d higher was associated with a 0.27-kg/m higher BMI (P < 0.01) and 0.54 kg more body fat (P < 0.01).</p><p><b>CONCLUSIONS: </b>Sodium intake was associated with higher BMI, WC, and body fat. Potassium intake was associated with lower BMI and smaller WC among US-born participants and participants with a longer duration of US residence.</p>