Damaged spermatozoa are supposed to be trapped in glass wool. In the respect of this, two glass wool filtration spermatozoa groups (0.5 cm, 1 cm depth) were compared with control group to assay sperm motility, HOS values, and vital rate by CFDA/PI staining method following glass wool filtration. The motility of canine sperm extended with PBS+PVP after glass wool filtration was lower in both filtrated groups than that of the control group (p<0.01) and the same significant difference was also shown in canine semen extended with Tris buffer (p<0.01). The motility of canine sperm diluted with PBS+PVP was higher than that diluted with Tris buffer in the same experimental groups (p<0.05). The motility of control group was not significantly decreased until 2 hours immediately after extending, however, the motility of both glass wool filtrated spermatozoa were significantly decreased as time passed until 2 hours after filtration (p<0.01). At each time for assay (immediately, 30 min, 2 hours after filtration), the motility of canine sperm of control group was higher than the filtrated groups (p<0.05), whereas the motility of 0.5 cm depth group was higher than 1 cm depth group at the immediate time after filtration (p<0.05), 30 minutes later (p<0.05) with no difference at 2 hours. No difference was shown among the experimental groups in HOS values of canine sperm after glass wool filtration. The vital rate assayed by CFDA/PI staining of both filter groups was higher than the control group (p<0.05).