We report spatiotemporal patterns induced by microscopic fluctuations in the Gray-Scott model. In the framework of stochastic kinetics, the macroscopic effect of internal noise of the system was investigated by simulating the reaction-diffusion master equation using Gillespie's algorithm. Pattern formation at the level of stochastic description is presented in comparison with that given by deterministic equations. Complex spatiotemporal patterns, including spiral waves, Turing patterns, self-replicating spots and others, which are not captured or correctly predicted by the deterministic reaction-diffusion equations, are induced by internal reaction fluctuations. Furthermore the intrinsic noise selects and controls the pattern formation with different intensities of fluctuation.