Three new species Trimmatothelopsis anthracina, T. knudsenii, and T. shandongensis are reported from the eastern coast of China, based on morphological, chemical and molecular data (ITS, LSU, and mtSSU). All three new species have IKI+ blue ascus. Trimmatothelopsis anthracina is characterized by carbonized apothecia, a biofilm at the immature apothecia base, and IKI+ blue turning red hymenial gel. Trimmatothelopsis knudsenii is characterized by rimose thallus, numerous reddish brown apothecia, and IKI+ blue turning red hymenial gel. Trimmatothelopsis shandongensis is characterized by dull brown thallus, thick hymenium, IKI+ red hymenial gel, and small asci. Comprehensive descriptions, detailed illustrations, and phylogenetic analysis of the new taxa are presented. Additionally, a worldwide key to Trimmatothelopsis species, including 21 species, is provided. Key words: Ascus stains, new species, saxicolous lichen, taxonomy.