Objective- To determine the possibility and reproducibility of three-dimensional ultrasonography (3DUS)and comparison of the achieved measurements to normal two-dimensional ultrasonography (2DCS)Design- Descriptive studyAnimals- 10 young mixed normal dogs, age 1.5-2.5 year, weighing 9.7-12 kg Procedure- Renal width, length, and depth measured in coron al and transverse sections. The measurementswere take n in both 2DUS and 3DUS scans. Eac h kidney was imaged five time s in coronal and tran sversesection and the measurements were recorded for each image.Statistical analysis-Descriptive analysis, paired t-testResults- The mean difference of the measurements obtained by 3DUS in compare with 2DUS was: 0.17em for renallength , 0.08 ernforrenal width , and 0.13 em for renal depth . There was no significant differencebetween 3DUS and 2DUS.Conclus ion and Clinical Relevance- In this study the correlation was seen between 3DUS and 2DUS.The3DUS method gives us extremely useful images for teaching and diagnosing purposes. The 3DUS image presentation can also be easily demonstrated in rotating 3Danimation.