Angelicae Pubescentis Radix (APR), a widely used traditional Chinese medicine (TCM), is mainly used to treat rheumatism and headache diseases. Angelol B is one of the bioactive constituents of APR with significant anti-inflammatory activity. This paper is aimed to illustrate the metabolites of angelol B in vivo. To achieve this objective, a metabolomics approach based on a rapid and accurate UPLC-Q-TOF-MS method was used to detect the metabolites of Angelol B in rat. A gradient elution system (ACN and 0.1% formic acid water) equipped with an Agilent SB-C 18 column (1.8 μm, 2.1 mm × 50 mm) to complete the separation. Scanning area at m/z 100−800 operated on an electrospray ionization (ESI). The data were collected in both positive and negative ion mode and analyzed by the Masslynx 4.1 and SIMCA 13.0 software. A total of 31 metabolites including 20 phase І and 11 phase ІІ metabolites were identified. Their structure and fragmentation process were deduced based on the MS and MS/MS data. All of thirty-one metabolites are new compounds based on the search of SCI-Finder database.