PURPOSE: To enable each user to receive the service of a file environment matched with each working environment by performing the relational file control applying the fuzzy control by means of a fuzzy assembly table.

CONSTITUTION: This system is provided with a storage 20 equipped with a fuzzy assembly table 3 and a file group 4, and a CPU 10 equipped with a file control means 2 which controls the file group 4 in the control of an operating system 1. Then the means 2 included in the system 1 obtains a common fuzzy assembly out of the table 3 consisting of the fuzzy assemblies given already to several propositions against a proposition given from a user and controls the file groups which are connected to each other in the ambiguous relation as a single unit. Thus each user can receive the service of a file environment matched with each working environment.