Cancer stem cells (CSCs) are a subset of tumour cells that possess self-renewal, differentiation, and tumour-initiating capabilities. They are responsible for tumour progression, recurrence, metastasis, and resistance to therapy. MicroRNAs (miRNAs) are short non-coding RNAs that regulate gene expression at the post-transcriptional level. They are critical modulators of CSC functions. miRNAs influence CSC behaviour and modulate key signalling pathways such as Wnt/β-catenin, Notch, Hedgehog, and PI3K/AKT, thereby affecting tumour initiation, progression, metastasis, drug resistance, and recurrence. miRNAs act as either oncomiRs or tumour suppressors, shaping the tumour microenvironment, altering responses to chemotherapy, and regulating key characteristics of cancer. They also alter the tumour microenvironment, regulate stemness, and determine therapy response. This chapter provides a comprehensive overview of miRNA-mediated regulation of CSCs across multiple cancer types, elucidates the molecular mechanisms of miRNA-CSC interactions, and provides an overview of the diagnostic and therapeutic implications.