African American emerging adults (age 18-29 years) tend to have poor asthma outcomes, possibly due to poor adherence to medication. Few studies have explored barriers to controller adherence in this population. This study utilized electronic daily diaries to assess barriers to adherence and asthma symptoms among 141 African American emerging adults with uncontrolled persistent asthma and poor adherence. Participants reported symptoms M = 3.43 days (of 7 days). They reported unintentional (e.g., forgetting) and intentional (e.g., choosing not to take) barriers to adherence, but forgetting, being too busy, and sleeping through a dose were the most common. Significant correlations were found between symptoms and barriers, as well as asthma control and medication adherence in the expected directions. Asthma symptoms and number of barriers were significant predictors of asthma control. Existing intervention strategies such as text-messaging may prove effective to address these barriers, but measuring and addressing adherence remains complex.