Abstract Predation-affected spatial pattern changes in a prey population were studied. The spatial pattern of a population of Galleria mellonella is changed by its predator, Podisus maculiventris. The pattern is affected by the frequency of attack by the predator (attack ability), the homogeneity of the attack ability within a predator population and the mobility of the predator. A mathematical model incorporating these three factors was constructed, and several computer simulations were conducted by changing the parameter values. A natural enemy population having high and homogeneous attack ability and high mobility effectively kills prey individuals.