An indoor position determination method and system based on WLAN signal strength using remote monitoring and cell space environmental attenuation is provided. The indoor position determination method includes a remote monitoring step of collecting information about signal strength from a neighboring AP and generating an AP signal strength table, a position information requesting step of receiving identification information and signal strength of a detected AP from a mobile terminal, and a cell determination step of comparing a signal strength pattern of each AP received from the mobile terminal with a neighboring AP signal strength pattern of each AP with reference to the AP signal strength table and determining a cell having an AP with a most similar pattern as a cell where the mobile terminal is presently located.