Background: The severity of arterial stiffness can be evaluated by pulse wave velocity (PWV). This study investigated the association between blood pressure (BP) control and arterial stiffness in middle-aged and elderly Chinese patients with hypertension. Material/Methods: Three hundred and twelve hypertensive patients were divided according to whether their hypertension was well-controlled or uncontrolled and stratified according to age. Arterial stiffness was evaluated by brachial -ankle pulse wave velocity (baPWV). The effect of BP control on arterial stiffness and its severity was assessed by multivariate linear and logistic regression analyses. Results: Moderate and severe arterial stiffness was detected significantly more often in patients with uncontrolled hypertension than in those with well-controlled hypertension, regardless of age. BaPWV increased by 8.467 cm/s in the study population overall for every 1-mmHg increment in systolic BP and by 8.584, 8.616, and 8.199 cm/s, respectively, in patients aged 45-65, 65-80, and 380 years. Regardless of age, the risk of arterial stiffness was 5.93 times higher (95% confidence interval 2.78-12.64) and the risk of a one-grade increase in the severity of arterial stiffness was 4.01 times higher (95% confidence interval 2.51-6.42) in patients with uncontrolled hypertension than in those with well-controlled hypertension. Conclusions: This study found a positive relationship between baPWV and BP and identified uncontrolled BP as a risk factor for arterial stiffness and its severity. Management of BP within a reasonable range may help to ameliorate arterial stiffness.