Packet storage method and packet storage apparatus

There is provided a packet storage method including: processing in which a sequence identifier is successively assigned to a packet captured from a network and the packet is stored in a buffer; creation processing in which the packet is read out from the buffer, a first identifier involved in a first property of the packet is identified, and an index data that mutually correlates the sequence identifier and the first identifier is created; and storage processing in which the packet corresponding to the sequence identifier included in the index data is read out from the buffer, the packet is sorted according to the first identifier included in the index data, and the sorted packet is stored in a storage unit on a per-first-identifier basis, executed by a processor.