An information management method to be executed by an information management apparatus, the information management method comprising: accepting a search request where latitude and longitude are specified, from a mobile device or a fixed device, for position information managed by the information management apparatus, and characterized by: generating one character string serving as one search key by alternately arraying one character of the latitude and another one character of the longitude, wherein each of the one character and the other one character is in a same digit regarding all of the digits of each of the latitude and the longitude, or regarding some digits from the least significant digit of each of the latitude and the longitude; and searching for a position key forward-agreeing with the search key, from a storage unit in which position information is stored in a manner correlated with position keys, the position information having been stored by: dividing a position range into a plurality of increment regions according to a precision of a latitude and a longitude used for specification of the position range; generating a group of the respective latitude minimum values of each of the plurality of increment regions, and of the respective longitude minimum values of each of the plurality of increment regions; for each increment region of the group, generating one character string by alternately arraying one character of the respective latitude minimum value and another one character of the respective longitude minimum value, wherein each of the one character and the other one character is in a same digit regarding all of the digits of each of the respective latitude minimum value and the respective longitude minimum value, or regarding some digits from the least significant digit of each of the respective latitude minimum value and the respective longitude minimum value; and storing the position information in the storage unit in a manner correlated with the respective character strings corresponding to the respective latitude minimum values and the respective longitude minimum values as respective said position keys. generating one character string serving as one search key by alternately arraying one character of the latitude and another one character of the longitude, wherein each of the one character and the other one character is in a same digit regarding all of the digits of each of the latitude and the longitude, or regarding some digits from the least significant digit of each of the latitude and the longitude; and searching for a position key forward-agreeing with the search key, from a storage unit in which position information is stored in a manner correlated with position keys, the position information having been stored by: dividing a position range into a plurality of increment regions according to a precision of a latitude and a longitude used for specification of the position range; generating a group of the respective latitude minimum values of each of the plurality of increment regions, and of the respective longitude minimum values of each of the plurality of increment regions; for each increment region of the group, generating one character string by alternately arraying one character of the respective latitude minimum value and another one character of the respective longitude minimum value, wherein each of the one character and the other one character is in a same digit regarding all of the digits of each of the respective latitude minimum value and the respective longitude minimum value, or regarding some digits from the least significant digit of each of the respective latitude minimum value and the respective longitude minimum value; and storing the position information in the storage unit in a manner correlated with the respective character strings corresponding to the respective latitude minimum values and the respective longitude minimum values as respective said position keys. dividing a position range into a plurality of increment regions according to a precision of a latitude and a longitude used for specification of the position range; generating a group of the respective latitude minimum values of each of the plurality of increment regions, and of the respective longitude minimum values of each of the plurality of increment regions; for each increment region of the group, generating one character string by alternately arraying one character of the respective latitude minimum value and another one character of the respective longitude minimum value, wherein each of the one character and the other one character is in a same digit regarding all of the digits of each of the respective latitude minimum value and the respective longitude minimum value, or regarding some digits from the least significant digit of each of the respective latitude minimum value and the respective longitude minimum value; and storing the position information in the storage unit in a manner correlated with the respective character strings corresponding to the respective latitude minimum values and the respective longitude minimum values as respective said position keys.