This study serves as a checklist of the myxomycetes of Trabzon and Giresun provinces, Turkey. Sixty-one myxomycete were identified, 20 of which were collected in the field and 41 grown in moist chamber culture. In addition, we report all taxa new for Giresun and Trabzon, including the following 15 taxa new to Turkey: Licea biforis Morgan, Cribraria intricata Schrad., C. macrocarpa Schrad., Lycogala exiguum Morgan, Arcyria globosa Schw.,.