The occurence of fungi associated with Lolium multiflorum Lam. seeds were examined in blotter test, in one handred samples from all 26 seed producing counties in the Rio Grande do Sul State. For identification, fungi structures were observed and measured both in seeds and in PDA cultures. Pathogenicity was tested in greenhouse, on plants and with seed inoculations. Effects on stand and dry weigth were evaluated. Among the fungi founded, Fusarium equiseti, Fusarium graminearum, Bipolaris sorokiniana, Drechslera oryzae and Pyricularia grisea showed pathogenicity to Lolium multiflorum and caused stand recuction. The higher losses of dry weigth were caused by P. grisea and F. equiseti.