The influence of multiplicative fluctuations of parameters of reactiondiffusion system on example of Gierer–Meinhardt model to formation of dissipative structures in soft mode instability regime was investigated. The system described interaction of nondecreased modes (order parameters) was received. It was shown that fluctuations of parameters are lead to changing of number of unstable modes, shifting of their eigenvalues and parametrical excitation of the system. The numerical simulation of described model evolution was received.