In the present paper, a hybrid method is proposed for calculating broadband strong motion seismograms in near-field massive earthquakes. For this purpose, simulated broadband (0 – 10 Hz) seismograms were formulated by combining high-frequency scattering seismograms (HF), with low-frequency certain seismograms (LF), and finite-fault earthquake failure models existing in three-dimensional ground model were investigated. Site-specific Green functions of high-frequency scattering seismograms (HF) for a heterogeneous environment with randomly distributed isotropic scatters were convolved with source-time function which characterizes and describes the failure process expansion. Then, using optimization in the frequency domain, these scattered seismograms were correlated to (LF) certain waveforms to match their amplitude and phase spectrum within the target interface frequency. Environmental scattering, failure attenuation (ηs), inherent attenuation (ηi), and site-specific kappa determine frequency-dependent attenuation, waveform, and spectral characteristics of the synthetic seismograms (HF) and hence affect the hybrid broadband seismograms. The proposed method was implemented for the Bam Earthquake (2003) and validation of the near-surface record acquired at Bam Station showed that the proposed technique can reproduce waveform of real broadband waves appropriately. This new hybrid method for simulating ground motion offers an applicable technique to any complex earthquake source for the analysis of seismic risk and estimation of ground motion. Engineers need an accurate estimation of strong ground motions resulted from potential future earthquakes to design structures that can survive anticipated levels of vibration.