In order to better study the channel assignment problem, a function from the vertex set to the set of all nonnegative integers is generated, that is the L(2,1)—labeling of a graph. Let the least label be zero, the L(2,1)—labeling number of a graph is the smallest number over the spans of all L(2,1)—labeling of this graph. Aiming at the problem of the L(2,1)—labeling numbers of the bracelet graph, which is a generalized graph from Cartesian products of the path and cycles, the definition of the bracelet graph is given, which is obtained by overlapping the two ends of a similarity ladder. At the same time the definition of the L(2,1)—labeling numbers is given. The L(2,1)—labeling number is completely determined by vertex grouped labeling method according to the difference of the circles' numbers and the vertices' numbers of the circles. The types of graphs are enriched and the labeling number theories are perfected.