Although many Multi-Join query optimizations algorithms have been proposed, there is a lack of cyclic multi-join query optimization algorithms. In this paper, a graph-based cyclic multi-join query optimization algorithm-Improved Minimum Result Relation-Minimum Weight First (Improved-MR-MWF) was proposed. The time complexity is O(mn). This algorithm, considering the influences among the join operations concerning same relation, chooses the join that the result relation is minimum as the top-priority operation. The minimum weight join among the top-priority operations was selected. The experimental results indicated that the cost and the query response time of the new algorithm were less than that of others.