In this study,we derived the analytic expressions of seismic moment caused by an arbitrarily orientated general dislocation model containing both shear and tensile components.Based on these analytic expressions,we propose an innovative algorithm to estimate the source parameters from the "observed" seismic moment tensor,which contains generally both double-couple and non- double-couple components.Through numerical simulations,we verified this new estimation algorithm of seismic source parameters is accurate,robust and very efficient.Therefore this new algorithm could have wide applications in the studies of complex source process of earthquake or nuclear explosion,as well as the micro-seismic events in energy exploitation and mining.