Objective:To study the effect of vitamin D deficiency on airway inflammation in rats with asthma. Methods:Sixteen Sprague-Dawley rats were divided into 2 groups randomly,including normal control group and vitamin D deficiency experiment model group,with 8 rats in each group. On days 1 and 7,the rats were sensitized with ovalbumin via introperitoneal injection and challenged with daily ovalbumin inhalation for 7 consecutive days since day 14. After the challenge,the bronchial alveolar lavage fluid (BALF) was collected for examining the total cell number and eosinophil count,and the lung tissue was taken to evaluate the airway inflammation. Results:Compared with the control group,the total BALF cell count and eosinophil percentage were found to increase in the vitamin D deficient model group (P < 0.05). More serious pathological changes and asthmatic airway inflammation were found in the lung tissues of rats lack of vitamin D. Conclution:Vitamin D deficiency could give rise to more frequent asthmatic attack and aggravate airway inflammation in asthmatic rats.