The Brahman cattle is mainly used for breeding and the meat industry. The present chapter had the objective of evaluating the physical and testicular development, and the serum testosterone level of 8-18 months old male Brahman cattle on grazing weight gaining performance tests. In Bos indicus, puberty usually occurs between the ages of 16 and 18 months. Variables such age, weight, and scrotal circumference were equally important in the estimation of sexual maturity in male Bos indicus. An increase in serum testosterone level occurred between 12 and 14 months of age, followed by testicular and body growth. An elevation in testosterone levels is an indicator that an acceleration in physical and testicular growth is approaching. The variables body weight and scrotal circumference which are important in the estimation of sexual maturity are dependent on testosterone levels in zebu cattle according to literature. It is recommended to calculate body mass index and testicular volume to follow male growth due to the high correlation between these variables.