The application of three main aspects of plant molecular biology due to plant improvement comprising molecular biology, DNA technology, and plant tissue culture will be introduced. In addition, plant gene mapping, plant molecular marker, and the making of transgenic plant will be acquainted. Prior to the plant biotechnology techniques, a brief explanation about basic plant physiology, agronomy, plant disease, pest and weed will be given. Furthermore the new updates of GMO (genetic modified organism) development in agricultural plant, including pro and contra opinion and facts, will be discussed