Eriophyoid mites from plum trees (Prunus domestica L.) in Hamadan Province, northwestern Iran, were collected during a survey in 2018–2020. Altogether 12 species, belonging to eight genera and two families, are reported herein. Five species are new to science and five species are new records for Hamadan province of Iran. The collected mites according to their families, genera and species are as follows: family Diptilomiopidae: Quadracus reticulatus sp. nov., Rhinophytoptus nemalobos Lotfollahi & de Lillo, 2014, Diptacus hamedanicus Jafari & Khanjani, 2020, Diptacus gigantorhynchus (Nalepa, 1892); family Eriophyidae: Acalitus iranicus sp. nov. causes small irregular galls around of buds, Aculus flechtmanni sp. nov., Aculus fockeui (Nalepa & Trouessart, 1891), Eriophyes prunorum sp. nov. causes blisters on leaf surface, Eriophyes savagei Keifer, 1939 causes leaf nail galls, Phyllocoptes hamedi sp. nov., Phyllocoptes abaenus Keifer, 1940, and Tetra pruni Jafari, Khanjani & Ueckermann, 2020.
