The purpose of this study was to assess the usefulness of radiographic examination of the splenomegaly associated with drug-induced splenic congestion and to establish the standard goal of the splenomegaly in dogs. Radiographic images of spleen in normal dogs were collected to determine the maximum diameter prior to, and 15 minutes after, administration of acepromazine, ketamine/diazepam combination, or propofol. Significant splenic enlargement was seen after administration of acepromazine, but statistical signalficant was found in a ventrodorsal view only. Splenic size tended to decrease after administration of ketamine/diazepam combination. Significant splenic enlargement was not found after administration of propofol. These results suggest that measurable splenomegaly can be detected by radiographic examination after some kind of drug administration and the evaluation of splenomegaly is more useful at ventrodorsal view than lateral view.