We describe an unusual occurrence of bilateral conjunctival tumours in a 25-year-old woman. This was the first sign of relapse of acute monoblastic leukaemia. There was also both marrow relapse and subsequent skin infiltration. No central nervous system involvement was detected. The tumours appeared as pink raised lesions in the upper conjunctivae of both eyes. They were not associated with pain or visual impairment. Conjunctival tumour biopsy revealed a dense mononuclear cell infiltration. Complete remission (conjunctival tumours, skin infiltration and bone marrow) was attained following systemic chemotherapy in combination with intrathecal chemotherapy.