The study aimed to establish a strategy to elucidate the in vivo constituents of Angelicae Pubescentis Radix (APR, also known as Duhuo) and reveal the probable mechanisms underlying its anti-rheumatoid arthritis activity. First recorded by Shennong Bencao Jing, APR is mainly used to treat Bi syndrome. Eleven absorbed components of APR were successfully identified using the rheumatoid arthritis (RA) rat model and the UHPLC-QTOF/MS technique. Two active ingredients (osthole and columbianadin) and five corresponding targets (PTGS1, PTGS2, RXRA, CCNA2 and ACHE) were found to construct a compound-protein interaction network in RA. In addition, a non-alcoholic fatty liver disease pathway, which was related to anti-RA activity, was eventually identified by KEGG analysis. Subsequently, molecular docking was performed by establishing a mixed matrix network, including the absorbed component, corresponding target and signaling pathway with two key compounds (osthole and columbianadin) and two important targets (PTGS2 and PTGS1). The result of molecular docking is in agreement with the network pharmacology.