Objectives: Understanding the interactions between allergic rhinitis (AR) and asthma is important for asthma management. This study explored the clinical features of AR as a comorbidity in Chinese asthmatic patients and its impact on asthma control. Methods: This cross-sectional survey was conducted among 20 051 patients with asthma in an out-patient setting and covered all of the territories of China. The patients were interviewed face-to-face. A standardized questionnaire was completed by each patient. AR was defined according to the ARIA criteria. The level of asthma control was assessed by the Asthma Control Test. A score <= 19 indicated poorly controlled asthma. Results: AR was present in 69.9% of patients with asthma. Of them, 72.4% had intermittent symptoms, and 93.1% presented with moderate/severe symptoms. Cold air, irritant air and household mites were the most common triggers for AR. A higher percentage of patients with AR experienced poorly controlled asthma compared with those without AR (56.2% versus 51.5%, p50.001). AR was associated with an increased risk of poorly controlled asthma [odds ratio (OR): 1.21, p < 0.001]. Moderate/severe or persistent symptoms were associated with a higher risk of poorly controlled asthma than those with mild or intermittent symptoms (OR: 2.34 and 1.78, respectively, p < 0.001). In contrast, diagnosed AR (OR: 0.84, p < 0.001), being currently treated with medication (OR: 0.91, p = 0.004) and a prior skin prick test (OR: 0.90, p = 0.003) showed a significantly negative association with poorly controlled asthma. Conclusion: This study confirms that concomitant AR and asthma are highly prevalent in China and that AR is associated with poor asthma control.