Patients who received a long-term drug therapy, including calcium channel blockers, antiepileptic and immunosuppressive drugs, often suffered from drug-induced gingival overgrowth (DIGO). However, the pathogenesis of DIGO remains unclear to date. A number of research found that DIGO is relevant to apoptosis and cell proliferation. Research progress on the relevance between drug-induced gingival overgrowth and the apoptosis and cell proliferation is summarised in this paper.