Renal length, width, and ratio to the length of the second lumbar vertebrae body were assessed on survey radiographs and excretory urograms in 50 Korean domestic cats. Renal dimensions on plain radiographs were: right kidney length $4.31{pm}0.50cm;(mean{pm}SD)$, right kidney width $3.10{pm}0.36cm$, left kidney length $4.17{pm}0.48cm$, left kidney width $3.03{pm}0.34cm$, right kidney length ratio $2.37{pm}0.21$, right kidney width ratio $1.71{pm}0.15$, left kidney length ratio $2.30{pm}0.20$, and left kidney width ratio $1.38{pm}0.08$, respectively. Renal dimensions on excretory urograms were: right kidney length $4.56{pm}0.53cm$, right kidney width $3.29{pm}0.37cm$, left kidney length $4.43{pm}0.47cm$, left kidney width $3.22{pm}0.33cm$, right kidney length ratio $2.51{pm}0.22$, right kidney width ratio $1.81{pm}0.17$, left kidney length ratio $2.45{pm}0.20$, and left kidney width ratio $1.78{pm}0.16$, respectively. There were significant difference in renal size and renal dimension ratio measured from contrast studies compared with survey radiographs (P<0.05). There were also significant difference in renal size and renal length ratio between right and left kidneys (p<0.05).