In general, the predator-prey model has been studied as a model of struggle for existence in a ecosystem. While conventional papers have focussed on the population change of the predator-prey, this paper focused on controlling the energy needed for the predator to pursue the prey. For simplification, assume the environment which there are only single predator and prey. Based on the environment, a certain amount of energy needed for a predator to pursue the prey was suggested on a basis of physical theories and also the used energy model was suggested on a basis of the simulation. From experiments, it was proven that the suggested energy models were appropriate for natural pursuit.