The invention provides a computer emulation method for sea-surface imaging of a bistatic synthetic aperture radar, and relates to the technical field of synthetic aperture radar imaging and the field of oceanography. The method simplifies and decomposes emulated true scenes into seven suitable computer emulations in an approximation degree, namely, emulation of sea-surface waves, emulation of tiltmodulation generated by wave surfaces of first-scale waves, emulation of fluid power modulation generated by interaction between sea-surface waves, sea-surface bistatic correlation time simulation, divided wave spectrum emulation, sea-surface bistatic electromagnetic scattering emulation, and sea-surface synthetic aperture radar image emulation, and develops software to solve the problems one byone to generate a final emulated bistatic synthetic aperture radar sea-surface image. The method takes files as ports, integrates emulation problems of several subjects, and not only meets the requirement of final emulation, but also facilitates the development of software modules.