The Jintiange capsule (JTG) has been clinically utilized for the treatment of rheumatoid arthritis (RA) for several decades. However, its mechanism of treating RA remains elusive. This study aimed to elucidate the therapeutic mechanism of the JTG in RA treatment through network pharmacology and bioinformatics approaches. Network pharmacology identified four active components and 16 overlapping targets of JTG. GO and KEGG analyses indicated involvement in cell proliferation, protein binding, C-type lectin receptor signaling, and dopaminergic synapse pathways. Differential gene expression analysis identified FBN2, TPT1, CALM3, CA2, and COMT as having significant diagnostic efficacy for RA. Single-cell transcriptome analysis categorized six cell types, with monocytes clustering into three distinct subtypes. These subtypes had different roles in RA regulation, governed by various transcription factors. The study suggests that active components from JTG interact with target proteins to influence the differentiation and functionality of immune cells, particularly monocytes, in RA. This offers preliminary insights into the underlying mechanism of JTG in RA treatment.