The present study aimed to identify the moss flora of the Osmaneli (Bilecik) district. As a result of the identification of moss specimens collected from the research area between 2006 and 2009, a total of 90 taxa belonging to 17 families and 38 genera are defined. Of these, twenty-eight taxa are reported for the first time from A1 grid-square and nine taxa are reported for the first time from A2 grid-square in the system adopted by Henderson. Grimmia lisae De Not., Schistidium pruinosum (Wilson ex Schimp.) G.Roth, Dialytrichia mucronata (Brid.) Broth., Tortula viridifolia (Mitt.) Blockeel and A.J.E.Sm., Leskea polycarpa Hedw., Pseudoleskeella rupestris (Berggr.) Hedenas and L. Soderstr. and Neckera pumila Hedw. are recorded for the second time from Turkey.