Little is known about how pediatric providers assess parental health literacy, how concordant they are with validated measures of health literacy, and how these perceptions may influence treatment recommendations, how instructions are given or how reliable they perceive parents to be in carrying out instructions. Two hundred and eighty-one parents of 6-12-year-old asthma patients attending a pediatric clinic visit were recruited to a cross-sectional study of health literacy and asthma outcomes. Fourteen pediatric healthcare providers participated. Parents completed surveys that included 2 measures of health literacy: the Test of Function Health Literacy in Adults (TOFHLA) and the Rapid Estimate of Adult Literacy in Medicine (REALM). Immediately postvisit, pediatric providers completed a brief survey asking their assessment of the parent's health literacy and how it impacted treatment instructions and recommendations. Kappa statistics tested concordance; chi square and logistic regression tested associations among provider ratings, rating concordance, and demographic factors. Six providers were interviewed regarding the bases for their ratings. Providers' perceptions influenced asthma treatment recommendations ( p = 0.001) and how treatment instructions were given ( p = 0.001). Providers indicated that their perceptions were shaped by parent's verbal communication skills and patterns of past behavior related to children's asthma management. Data from 277 parents indicated that most had adequate health literacy with a lower percentage scored as adequate by the REALM versus the TOFHLA. Pediatric provider estimates of parental health literacy had low concordance with the validated measures. Providers were more likely to designate whites as adequately health literate. Pediatric asthma providers' perceptions of parents' health literacy can influence treatment recommendations and instructional practices.