Many clinicians use the same solution, most often normal saline, to cleanse the periwound skin and the wound bed itself. However, skin debris such as water-insoluble proteins and lipids are not efficiently removed by normal saline solutions. To analyze the skin debris and micro-organisms found on the periwound skin of pressure ulcers and to evaluate the effect of periwound cleansing on the microbial flora, a descriptive study was conducted among 17 long-term care residents with Stage III and IV pressure ulcers. Skin debris from both the periwound area and normal skin was collected from all 17 residents. In addition, micro-organisms from the wound bed, periwound, and normal skin of five residents were collected before, immediately after, and 6 hours and 24 hours after periwound cleansing using a skin cleanser. All microbial species were identified by cultivation. Cholesterol and nitrogen-containing substances were found in greater quantity on the periwound than on normal skin (P = 0.0027 and P = 0.0054, respectively) and the number of isolated micro-organisms from the periwound area was larger than that from normal skin. Protein showed the highest correlation to the microbial count present on the periwound (r = 0.71, P = 0.0014). The microbial counts of all isolated micro-organisms decreased immediately after cleansing but the number of isolates with high microbial counts increased over time. In the wound bed, the number of isolates with decreasing microbial counts was larger than the number of isolates with increasing microbial counts. Both numbers returned to pre-cleansing values after 24 hours, suggesting that periwound cleansing only (without directly cleansing the wound bed) is effective at reducing the microbial counts in the wound bed for up to 24 hours. Further research is needed to evaluate the effects of periwound cleansing on healing time.