Background: Serum or cord blood soluble Fas ligand (FasL) has been related to asthma, allergic rhinitis, and atopic dermatitis in cross-sectional and short-term follow-up studies. However, the association of cord blood soluble FasL with long-term allergic outcomes has seldom been investigated. Thus, this study investigated the relationship between cord blood soluble FasL and long-term allergic outcomes in a follow-up birth cohort. Methods: The Prediction of Allergies in Taiwanese Children birth cohort study recruited healthy newborns upon delivery. At birth, blood was collected from the umbilical cords of these children, and the cord blood soluble Fas ligand levels were measured. At the age of seven years, the allergic outcome of each child was diagnosed by pediatric allergists and pulmonologists. Tests were conducted to measure the specific immunoglobulin E, fractional exhaled nitric oxide (FeNO), and pulmonary function levels of each child. Results:Cord blood soluble FasL levels were higher in 7-year-old children with allergic rhinitis (Odds ratio [OR] = 2.41, p = .012) and expiratory airway obstruction (the highest forced expiratory volume in 1 second/ forced vital capacity < 90%, OR = 2.11, p = .022). The FeNO and Dermatophagoides pteronyssinus-specific immunoglobulin E levels of 7-year-old children were positively correlated with cord blood soluble FasL levels (p = .006 and .02, respectively). Conclusion: In this birth cohort, the cord blood soluble FasL levels were associated with allergic rhinitis, obstructive-type lung function, FeNO, and house dust mite sensitization in 7-year-old children. The cord blood soluble FasL level might be used as a predictor for allergic diseases in children who are 7 years old.