Abstract: Introducing five Impact problems on mankind, this paper focuses on the energy and environmental probems. The energy which utilized and recognized by mankind may be classified into five categories. (1) mechanical energy (potential and kinetic energy), (2) thermal energy, (3) electrical energy, (4) radiation energy (5) structural energy of matter (chemical bond energy and neuclear energy). Jhree principles of utilization of energy must be followed. (1) maximun amount of energy converted from minimum amount of energy resource, (2) maximun best quality of goods produced by minimum amount of energy, (3) mininum effect on the ecosystems and relation to their environment fron the utilization of energy. In considering a question in eighr its aspects, the paper analyses the correlations between environmental pollution and exaggeration or abusive utilization of energy. Therefore, conservation of energy and reasonable use of energy are best methods for environment control.