1. A method of processing various processing requests by speech such as by telephone for a transaction, which comprises the steps of: receiving the processing request from a processing requester; then, executing a data storage area making step for making a processing request data storage area in a predetermined region of a storing means with the processing request being distinguishable from other processing requests; executing receiving steps of receiving the contents of conversation of the processing requester with dividing the contents into predetermined content portions; executing a speech signal quantizing step for quantizing speech signals of the conversation contents, thus converting them into digital speech data if the conversation contents received at each said receiving step belongs within a predetermined first conversation content class; executing a speech signal character string converting step for generating character string data of speech data based on the speech data of the conversation contents if the conversation content belongs within a predetermined second conversation content class; and for all of the divided conversation content portions, executing a storing step of storing the digital speech data or the character string data in the data storage area either separately upon completion of said each speech signal quantizing step or said each speech signal/character string converting step or in batch upon completion of all of the speech signal quantizing steps and the speech signal/character string data converting steps.