To investigate the genetic diversity of escaped tilapia in main aquaculture area of Guangxi, the present study compared and analyzed mitochondrial Dloop control region sequences from Yulin, Nanning, Qinzhou, Guigang, Fangchengang, and Beihai. Using polymerase chain reaction(PCR)and sequencing, the Dloop sequences of tilapia from Yulin, Nanning, Qinzhou, Guigang, Fangchengang and Beihai were obtained. By sequence comparison, construction of phylogenetic tree and other bioinformatics analysis, the genetic diversity of Dloop was discussed in different area of tilapia. The sequence results showed that the A, G, T, C ratios were 32.05%, 20.79%, 33.19%, and 13.97% respectively in Dloop from tilapia. Among them, the C ratio was the lowest and T ratio was the highest. The C+G ratio of 34.75% was lower than the A+T ratio of 65.25%. In total, 140 mutation sites were found including 79 transitions, 42 transversions and 19 inserts(deletions). The ratio of substitution and inserts(deletions)were 6.39. The conserved sequences of CSB2, CSB3 and CSB1 were identified from the Dloop sequences from tilapia. Phylogenetic analysis shows that the value of genetic distance were smaller than other comparisons in Nanning and the distance between Nanning and reference sequences was the smallest indicating the low degree of differentiation in this area. High genetic distance was found in escaped tilapia in Qinzhou and the fish in Qinzhou were clustered in one twig indicating the tilapia in Qinzhou had significant genetic differentiation compared with the tilapia in other areas