Stress and distress have been suggested to prolong difficult-to-control asthma (DTCA), that is, asthma that is not under control despite optimal medical treatment. A pediatric pulmonologist referred a 16-year-old girl with DTCA in whom asthma-specific fear induced by disturbed memories and distorted cognitions following frightening asthma attacks were driving asthma exacerbations. We examined whether cognitive-behavioral therapy (CBT) and eye movement desensitization and reprocessing (EMDR) focusing on asthma-specific fear and disturbed memories could reduce asthma symptoms and its burden. The single-case experimental design included 48 weekly assessments of primary outcomes during all phases, and 4 assessments of secondary outcomes at intake, pretherapy, posttherapy, and follow-up. Analysis of the time series data with a piecewise regression model demonstrated that the level or slope (trend) showed an improvement during the intervention and a sustained improvement during follow-up on all primary outcomes: burden of asthma exacerbations, physical activities, social activities, physical complaints, and worrying. Analyses using the Reliable Change Index showed significant pretherapy to posttherapy changes on most domains of questionnaires measuring secondary outcomes: Asthma Control Test, Pediatric Asthma Quality of Life Questionnaire, Child Behavior Checklist, and Youth Self-Report. Moreover, use of rescue medication went down and lung function (FEV1) came just into the normal range at follow-up. The study showed that asthma symptoms and the burden of asthma were reduced after CBT and EMDR. This proof-of-principle study suggests that DTCA may improve by psychological interventions in pediatric patients with psychological stress or distress.