There were little national data on hypertension based on the oldest-old, and lack of information on chronological changes. This study aimed to describe trends of blood pressure (BP) levels and hypertension prevalence for the past 16 years among the oldest-old in China. All the oldest-old who had participated in the Chinese Longitudinal Healthy Longevity Survey (CLHLS) 1998 to 2014 with information about BP levels and hypertension were included in the analysis. There was fluctuation over the past 16 years for both SBP and DBP levels. The mean SBP level decreased from 148.4 ± 24.4 mmHg in 1998 to 130.8 ± 18.7 mmHg in 2005, and then increased to 139.7 ± 22.0 mmHg in 2014. The mean DBP level decreased from 84.3 ± 13.4 mmHg in 1998 to 78.9 ± 11.7 mmHg in 2008, and then increased to 79.7 ± 11.8 mmHg in 2014. The hypertension prevalence increased from 43.1 to 56.5% for the 16 years. The prevalence of isolated systolic hypertension was lowest in 2002-2005 (14.3%), and then increased to 30.7% in 2014. Multivariate logistic regression showed that older age, lower education and economic level, without health insurance were associated with higher hypertension prevalence. There was a significant increase in hypertension prevalence among the Chinese oldest-old from 1998 to 2014. Greater efforts are needed for hypertension prevention among this specific population.