Abstract Rheumatic diseases, such as rheumatoid arthritis and systemic lupus erythematosus, represent a complex and heterogeneous group of immune‐mediated disorders. Traditional research approaches have been limited in their ability to comprehensively elucidate the pathogenesis and individual variability of these conditions. This review evaluates the application of single‐cell RNA sequencing (scRNA‐seq) technology in the study of rheumatic diseases. scRNA‐seq allows for transcriptomic profiling at the individual cell level, enabling the assessment of cellular heterogeneity and molecular mechanisms underlying disease. The use of scRNA‐seq has revealed significant alterations in gene expression profiles across various immune cell types—including T cells, B cells, and macrophages—in patients with rheumatic diseases. Furthermore, distinct functional differences among cellular subsets have been identified, providing new insights into disease‐specific immune dysregulation. Single‐cell sequencing technology enhances our understanding of the pathogenesis of rheumatic diseases and offers valuable implications for individualized treatment strategies. It holds promise for improving early diagnosis and advancing precision medicine approaches in rheumatology.