The aim of the study was to evaluate the association between weight status and asthma, allergy and respiratory symptoms in young adults with bronchiolitis in infancy. At age 26-29 years, a questionnaire was sent to 78 study subjects hospitalized for bronchiolitis at age <24 months, and 59(76%) of them answered. Asthma, allergy and respiratory symptoms were compared between overweight or obese and normal weight groups constructed by body mass index (BMI). Corresponding data were available from the follow-up visit at age 18-20 years. Population controls matched for sex and birth month and place were recruited for this 26-29 years study. Thirty-two study subjects (54.4%) were overweight (BMI >25 kg/m2) and 8(13.6%) obese (BMI >30 kg/m2) at age 26-29 years. Overweight was present in 21/52 study subjects (40.4%) at age 18-20 years. Overweight or obesity had no association with doctordiagnosed or self-reported asthma or allergy, or the use of inhaled corticosteroids, at either age. The negative results were confirmed by adjusted analyses at age 26-29 years. Overweight or obesity at age 18-20 years did not predict asthma 8 years later. Overweight or obesity had no association with asthma or allergy in young adults hospitalized for bronchiolitis in infancy.