Abstract:After the red imported fire ant (RIFA), Solenopsis invicta Buren was introduced to the lawn, it could settle down and enlarge its population in a short time. RIFA could change the structure of ant community in this invasion area. Through the analyses of predominant ant species in every different invasion periods, the predominant ant species in treatment was different from that in CK. RIFA could substitute for former predominant ant species after its invasion, and had an absolute predominance in population. The results showed that when RIFA invaded the lawn, the ant community diversity index and evenness index declined, and the predominance index in this area was rising. Ant community similarities in each treatment were compared, and it was found that in the area where RIFA slightly invaded and the CK, the comparability coefficient (q) was between 0.25 to 0.50, which was not similar. The comparability coefficient (q) for the area with moderate RIFA and the CK, was between 0.075 and 0.444, which was a middling dissimilar or extraordinarily dissimilar; And that for the area which serously invaded and CK, the comparability coefficient (q) was between 0.0 to 0222, which was extraordinarily dissimilar. It was showed that different endangered districts had different effects on the native ant community. The bigger the population of RIFA was, the greater effect on native ant community it had, and the less time it took for the RIFA to substitute for native ant species.