【Background】Common ragweed, Ambrosia artemisiifolia has successfully invaded Laibin, Guangxi, and it has impacted significantly local biodiversity, agricultural industry and resident′s health. Both Ophraella communa and Epiblema strenuana are important special natural enemies of A.artemisiifolia, and the two natural enemy species had suppressed the spread of A.artemisiifolia in Hunan Province, etc. 【Method】In order to explore the combined control effect of O.communa and E.strenuana on A.artemisiifolia, the two natural enemy species were released into the areas invaded by A.artemisiifolia in Laibin, Guangxi, on May 24, 2009 (densities of the two natural enemy species were 1170 individuals·hm-2). 【Result】The mortality of A.artemisiifolia plants was up to 98% on August 29, 2009, and the two natural enemy species spread to the adjacent areas invaded by A.artemisiifolia rapidly. The effect of the two natural enemy species on A.artemisiifolia was 50%~60% in the spread areas. 【Conclusion and significance】The two natural enemy species had a significant control effect on A.artemisiifolia, it′s suggested that biological control technique of A.artemisiifolia with O.communa and E.strenuana can be applied in Guangxi Province.