Abstract： Objective:To analyze the trajectory of waist-to-height ratio (WHtR) from childhood to adulthood and its association with the risk of hypertension in adulthood.Methods:In this retrospective cohort study, based on the data of China Health and Nutrition Survey (CHNS) from 1991 to 2015, the group-based trajectory model was applied to identify the trajectory of WHtR in 1 794 subjects aged from 7 to 40 years living in 15 provinces, autonomous regions and municipalities in China. The subjects aged 18 years and above with a systolic blood pressure≥140 mmHg (1 mmHg=0.133 kPa) or diastolic blood pressure ≥90 mmHg or those currently taking antihypertensive drugs were defined as having adult hypertension. And further, the Poisson regression model was used to assess the effect of WHtR trajectory from childhood to adulthood on adult hypertension, and the “E-value” approach was employed to evaluate the potential impact of unobserved confounders on the robustness of the results.Results:Of all the subjects surveyed, 3 trajectory groups were identified, and 750 (41.8%), 958 (53.4%) and 86 (4.8%) subjects were identified as having persistent normal, slow-growing and fast-growing WHtR trajectory, respectively; the incidence of adulthood hypertension in the up-mentioned 3 trajectory groups was 2.1%, 4.7% and 14.0%, respectively ( P<0.001). The risk of adult hypertension in the slow-growing trajectory group ( RR=1.94, 95% CI: 1.12-3.36) and the fast-growing trajectory group ( RR=5.70, 95% CI: 2.65-12.24) were both significantly higher than that in the persistent normal group (both P<0.05). The results of sensitivity analysis showed that the results were relatively robust (E-value was 3.29 and 10.88, respectively). Conclusion:Different trajectories of WHtR from childhood to adulthood exist in the surveyed population, and the increase of WHtR would be positively correlated with the risk of adulthood hypertension.