Compared to the conventional reverse time migration（RTM），RTM of multiples has a higher imaging precision.Based on the analysis of the imaging principle and conditions of RTM of multiples，the paper studied the steps of multiples prediction，wave field extrapolation and so on in the imaging process of RTM of multiples. Then，the shot gathers with only multiples were obtained by applying the surface-related multiples elimination method based on feedback loop theory to the Sigsbee2B geological model，and the imaging processing of RTM of multiples was implemented based on the acceleration of multi-card GPU. The processing results show that the imaging result of the middle-shallow layer obtained by RTM of multiples is clear，and the imaging precision of shallow structures is obviously higher than that obtained by conventional RTM.Besides，the computational speed and efficiency can be improved significantly by the application of multi-card GPU，which makes it possible for the imaging processing of RTM of multiples based on big data.