This article aimed to discuss the changes in the testicular parenchyma, analyzed by the use of ultrasonography, and correlates them with the testicular biometric parameters and testosterone concentration in crossed Murrah x Mediterranean buffaloes. Nineteen buffaloes, with initial ages between 11 and 59 months,were submitted to fortnightly collections of semen for a period of six months. At each collection the testicular biometry and testicular echogenicity were evaluated as well as blood samples were also collected to measure the plasma testosterone levels. The data were submitted to analysis of variance by the GLM procedure, considering the age group fixed effect. The average data obtained were compared by the Duncan test, at 5% significance. There was a significant growth (P<0.05) of the scrotal circumference, which varied from 12.88±0.51 cmto 31.18±0.75 cm among animals aged 12 to 60 months, as well as testicular volume, which ranged from 30.28±17.37 to 611.96±38.69 cm³ among the animals. The echogenic intensity of the testicular parenchyma varied in pixels from 78.67±6.36 to 109.24±3.13 in animals aged 12 to 60 months respectively. In the animals with ages between 12 and 19 months was observed levels of testosterone considered being low, whereas in the animals from 20 to 21 months there was a progressive increase in the testosterone levels, which showed their peak in the animals older than 60 months. Therefore, through ultrasonography it was possible to detect differences in echogenicity among different phases of pre-puberty, puberty and sexual maturity in the animals, and this procedure seems to be an important tool in the selection of this characteristic.