Time reversal (TR) processing is derived from the invariance of the wave equation for lossless medium to change in the sign of the time variable. By retransmitting the TR version of the time‐dispersed received signal propagated from a probe source (PS) to a source‐receiver array, one can reacquire the transmitted pulse at the PS location (time compression and spatial focusing) when the waveguide environment is time invariant. However, if some environmental variations occur between the two transmissions, the retrofocusing signal will be defocused. This paper presents a new method of environmental parameter inversion by comparing the difference of the focused signals measured at the PS location with/without environmental perturbations. Because the sound speed profile (SSP) plays a critical role in an uncertainty ocean environment, inversion of the SSP represented in terms of the empirical orthogonal functions is developed and discussed in detail. Simulations demonstrate some advantages of environmental inversion via TR: (1) great signal‐to‐noise ratios can be obtained at the PS location; (2) variations of the environment at different times can be directly inverted by repeatedly retransmitting either the same received signal generated by one PS transmission or the updated received signals generated by updated PS transmissions.