The present invention discloses a filter medium for removing leukocytes from a leukocyte-containing sample and a filtering method thereof. The filter medium comprises a base material and a first polymer. The first polymer forms cross-linked networks or polymer brushes on the base material and comprises charged groups or latent charged groups to control the electrical characteristic of the first polymer. The surface of the base material formed with the first polymer possesses a specific charge distribution.本發明係提供一種白血球過濾材料及其過濾方法,白血球過濾材料包含:一基材;以及一第一聚合物,以交聯的網絡狀或刷子狀形成於該基材上,該第一聚合物包含複數帶電基團或潛在性帶電基團;其中,該基材的形成有該第一聚合物之表面具有一特定的電荷分佈。
