Single‐cell RNA sequencing (scRNA‐seq) is a novel method enabling genetic characterization of tumor tissue at a single‐cell level. This study systematically reviewed the literature on studies using scRNA‐seq to characterize head and neck squamous cell carcinomas (HNSCCs). Seven studies were included, of which two studies performed scRNA‐seq on 20 patients in total, and five studies used scRNA‐seq data in a subsequent clinical study. The former mentioned two studies found intra‐tumoral genetic heterogeneity among malignant cells but genetic uniformity among non‐malignant cells. The five latter studies used scRNA‐seq data in various ways. Three studies identified biomarkers related to predicting whether a patient would benefit from immunotherapeutic treatment. One study characterized genes related to the perineural invasion. One study identified genes to be used in diagnostics. Further studies performing scRNA‐seq on HNSCC are required to continue the ongoing development and use of scRNA‐seq.