The emerald ash borer, Agrilus planipennis Fairmaire, 1888 (Coleoptera: Buprestidae), is an invasive pest in Europe and North America, responsible for extensive mortality of ash (Fraxinus spp.). This study reports its first confirmed occurrence in Slovakia and summarises the subsequent delimiting survey. On 25 June 2026, specimens morphologically resembling A. planipennis were collected from a monitoring trap in a park in Streda nad Bodrogom, south-eastern Slovakia. Eighteen adults were identified as A. planipennis by the national quarantine diagnostics laboratory, with confirmation by the European Union Reference Laboratory in France. Initial field inspections revealed characteristic galleries and D-shaped exit holes on ash trees at the detection site, in nearby forests, and along roads within approximately 7 km. By 31 July 2026, 2250 survey points had been recorded, of which 149 showed evidence of A. planipennis, including adults, larvae, galleries, or exit holes. Old galleries together with living larvae indicate that the pest had probably been established in Slovakia for several years before detection in 2026. Symptom assessment was complicated by widespread ash dieback caused by Hymenoscyphus fraxineus (T. Kowalski) Baral, Queloz & Hosoya, 2014.