The objectives of this study were to evaluate the efficacy of uterine biopsy as a sampling procedure for bacteriological examination, and to assess the importance of obligate anaerobes in the bovine uterus. The aerobic and anaerobic uterine flora of cows with postpartum metritis, cows in postpartum period without metritis and repeat-breeder cows was examined by using swab and biopsy sampling techniques. Obligate anaerobes were isolated in all the 11 cows with postpartum metritis and in three of the five normal cows. No obligate anaerobes were isolated from the six repeatbreeder cows. There was a significant difference (p < 0.01) in the number of bacterial isolates obtained from samples collected by biopsy and by swabbing. A total of 72 isolates was obtained with the biopsies compared to 48 by swabbing. Obligate anaerobes make up an important part of the postpartum uterine bacterial flora, and it seems that in some instances uterine biopsy would be more satisfactory than swabbing for bacteriological examination of the uterus.