In southern China, elevated risk of all-cause and cardiovascular mortality was observed in relation to higher weight-adjusted-waist index (WWI) levels (≥11.2 cm/√kg). These observations, if corroborated by further studies, indicated that WWI may be a simple as well as effective anthropometric index in clinical practice.

• This study included 12,447 participants (mean age, 59.0±13.3 years; 40.6% men) to examine the association of WWI with all-cause and cardiovascular mortality in southern China.

• WWI was described as waist circumference (WC) divided by the square root of weight.

• WWI was found to have a nonlinear positive association with all-cause and cardiovascular mortality.

• A significant higher risk of all-cause death (HR: 1.36) and cardiovascular mortality (HR: 1.43) were observed in participants in quartile 4 (≥11.2 cm/√kg) vs those in quartiles 1-3 (<11.2 cm/√kg).

• No substantial changes occurred in the results after further adjustment for body mass index and WC.

• There were no significant interactions in any of the subgroups (gender, age, area, physical activity, current smoking, current alcohol intake, hypertension and stroke).