This study was performed to characterize the normal blood flow of the canine testis and to measure the peak systolic velocity (PSV), end-diastolic velocity (EDV), resistive index (RI) and pulsatility index (PI) of testicular arteries weekly during a period of 6 months in five healthy Beagle dogs and to evaluate whether there were any change along this time. The ultrasonographic exams were made with an 11 MHz linear transducer. The vessels of the testes were subdivided into three categories: supratesticular arteries, marginal artery and intratesticular vessels. At the supratesticular arteries, two measurements were recorded at the cranial and the looping parts. No significant differences in any of the parameters studied were observed for the 6 months that the study was performed. The cranial part of the supratesticular artery showed a flow pattern of high-resistive vessel, whereas in the looping part of the supratesticular artery, marginal and intratesticular arteries, the flow showed a low-resistance pattern. PSV, RI and PI values were higher at the cranial part of the supratesticular artery, followed by the looping part of the supratesticular artery, marginal and intratesticular vessels. EDV measurements were higher in the looping part of the supratesticular artery.