The present invention relates to a system 10 and method for identifying the position of cellular telephones 12 in a geographical area served by a mobile telephony network 14. The system 10 comprises a mobile location center 15 capable of analyzing information about the electromagnetic (RF) field transmitted by cellular telephones 12 with reference information including both RF information and probabilistic information associated with the morphology of the geographical area. The method involves assigning different weights to the location of cellular telephones 12 as a function of probabilistic reference information, and thus makes it possible to use statistical methods for resolving situations of ambiguity in locating cellular telephones which would otherwise be resolved in purely random fashion.