At first, Qian Xuesen´s treatises about technological science are presented in this paper. Technological science emphasizes particularly opening out the mechanism of the phenomenon, levels and relations and abstracting the principles, laws and methods applied at large in the field of engineering technology. Technological science drives the rapid progress of the engineering technology, as a bridge between the scientific discovery and the industry development. The characteristics of the development of recent technological science from the development of the information science are emphasized. (1) The development of technological science has extended to researching the law in the field of information from researching the law in the fields of matter and energy. (2) The infiltrating to basic science from information science has formed the new hotspot in technological science. (3) Information science has greatly improved the research environment for the traditional technological science. (4) Information theory, control theory and operation research form together the lever of the technological science of system science. The social values of the technological science are farther discussed from the aspects of the applied value, cultural value and spirit value.