The term ‘primary cutaneous lymphoma’ (PCL) refers to cutaneous lymphomas that present in the skin with no evidence of extracutaneous disease at the time of diagnosis. PCL is rare in children, comprising 5% of all cases. PCL is classified into three primary groups: cutaneous T-cell lymphomas (CTCL); cutaneous B-cell lymphomas (CBCL); and precursor haematological neoplasm. CTCL are the most common, accounting for 80% of childhood-onset PCL. Mycosis fungoides (MF) is the most common form of CTCL, with an overrepresentation of hypopigmented variants in the paediatric population. MF has been labelled ‘the great imitator’, illustrating the protean clinical manifestations of the disease; delays to diagnosis are therefore common. Paediatric survival in MF is usually excellent, as studies have consistently shown presentation in early-stage disease. Treatment modalities include phototherapy and topical corticosteroids, amongst other strategies. Other subtypes of primary cutaneous lymphoma are exceedingly rare in the paediatric population, but have been reported to varying degrees in the literature.