Human herpesvirus 8 (HHV-8) is associated with Kaposi sarcoma (KS), multicentric Castleman disease (MCD), and primary effusion lymphoma (PEL), important causes of morbidity among people living with HIV. Data on these diseases remain limited from Central and Eastern Europe compared with Western Europe. We conducted a multicentre cross-sectional survey, using an online questionnaire distributed to HIV physicians within the Euroguidelines in Central and Eastern Europe Network Group, comprising epidemiology, diagnostic capacity, and management of HHV-8-related diseases. Twenty-six HIV treatment centres from 22 countries participated, providing care for 36,845 people living with HIV. A total of 55 cases of KS (1.49 per 1000 PLWH) were reported, of which 35 (63.6%) had visceral involvement. MCD and PEL were uncommon, with 7 and 4 cases, respectively. Diagnostic capacity varied between centres: computed tomography was available in 80.8%, bronchoscopy in 30.8%, and gastroscopy in 23.1%. Antiretroviral therapy alone was the most common first-line treatment for limited KS, while pegylated liposomal doxorubicin was accessible as first-line and/or second-line treatment in 46.2% of centres. HHV-8-related diseases remain uncommon but clinically relevant complications of HIV infection in Central and Eastern Europe. Regional variability in diagnostic resources and treatment availability highlights the need for strengthened referral pathways and guideline-adherent care.