The conventional hyperbolic travel time is based on the hypothesis that offset is not larger than the depth of the reflector and is not suitable for velocity analysis and normal move-out of seismic data for the long cable acquisition mode with a large degree of migration and multi-folds. Based on these facts, we propose a long-array non-hyperbolic normal move-out(NMO)method and used it for the first time to process seismic data from the South China Sea. We introduced two parameters into this method, which are non-uniformity s and anisotropy η, in order to meet the requirements of seismic data processing with long cable acquisition. The results of both synthetic and field data for the non-hyperbolic NMO show that the seismic traces of a large offset and a steep dip angle are approximately aligned and the profiles have clear images and a high signal-to-noise ratio.