The invention relates to a method of quantizing coding and decoding and a device. The method mainly comprises: on quantizing coding end, if the nearest adjoint point value in a lattice vector is not in a basic code book, a processing mode of splitting the nearest addjoint point value is adopted to process a coding operation; corresponding, on quantizing decoding end, a correspnding processing mode is adopted to process a decoding operation. The invention embodiment can effectively improve processing efficiency in a course of quantizing coding and decoding via combining a basic code book coding mode and a scalar quantization coding mode.