The measurement to laser scattering characteristics of target is critical for estimation of laser measuring system performance.According to the evaluation requirements to radar scattering cross section of the complex-shape, full-scale large object, we performed an outfield measuring test, and made analysis to the measurement data through measuring experience and simulation calculation.Based on simulation modeling and the modes for target scattering property evaluation, some ideas were proposed for improving outfield measuring accuracy for radar scattering cross section of complex large object, which may be taken as a reference for research on laser scattering characteristics of large object, as well as the establishment of evaluation method for scattering cross section of radar.