Adhesively bonded techniques have been widely used to repair composite components in aircraft structures. However, large variations in bonded strength may occur due to variability of the manufacturing processes, which has impeded their further applications. In this present work, a Kriging surrogate model was established to predict the failure strength of scarf-repaired composites. Based on the validated Kriging model, the failure probability of scarf-repaired composites considering the uncertainties of adhesive properties was evaluated. Furthermore, the variance based global sensitivity analysis was performed to determine the influences of different adhesive properties on the failure strength of scarf-repaired structures. The importance order of different properties was given to provide guidance for structural design.