The purpose of this paper is to discuss the following three problems:
(1) the number of equivalent classes of fuzzy subgroups of a group G,
(2) the relationship between the number of equivalent classes of fuzzy
subgroups and the order of a cyclic group G, (3) the relationship bet
ween the order of fuzzy subgroups and the order of a cyclic group G, (
4) a classification of a group, using membership values of fuzzy subgr
oups, is given. (C) 1998 Elsevier Science B.V.