1. A vector quantization apparatus for performing coding of a target vector by multi-stage vector quantization, the apparatus comprising: a first quantizing section for performing a first stage of the coding of the target vector using a first code vector stored in a first codebook; an amplifier storing section for storing a scalar associated with a code of each first code vector, and a second quantizing section for determining a third code vector by multiplying a second code vector stored in a second codebook and the scalar together, performing distance calculation using the target vector, the first code vector and the third code vector, and performing a second stage of the coding of the target vector using a result of the distance calculation.