Increased body mass index (BMI) has been associated with an increased prevalence of asthma in children, however the association between BMI status and asthma severity has been less well defined. The aim of this study was to describe the association between childhood obesity and asthma severity, frequency of hospital and emergency department visits as well as pattern of aeroallergen sensitization. A retrospective study was conducted at pediatric outpatient clinics in University Hospital Sharjah. All consecutive patients aged 6 years and above, with confirmed diagnosis of asthma visiting the outpatient pediatric clinics during 2018 were included in this study. Sources of information were the patient's medical file, laboratory data, pharmacy data, as well as reports from the pediatric in charge. This study included 164 children with asthma. 63% of asthma patients were male. The vast majority of patients were from Arab ethnicities (n = 154, 94%), majority had mild asthmatic conditions (n = 133, 81%), and one-third were either overweight or obese (n = 52, 32%). Overweight or obese asthmatic children with BMI percentile of equal or more than 85% was associated with more asthma severity (odds ratio [OR]: 3.27, 95% confidence interval [CI]: 1.42-7.54; P = 0.005), as well as more frequent asthma related hospital visits (OR: 2.53, 95% CI: 1.22-5.26; P = 0.013). Overweight asthmatic children with BMI between the 85th and 94th percentiles and obese asthmatic children with BMI equal to or greater than 95th percentile are associated with more severe asthma phenotype and more frequent hospital and emergency department visits.