The introduction of invasive species is increasing worldwide due to the development of the trade and the pet industry. Geckos (Gekkonidae) are the representative invasive reptiles. In the Republic of Korea, two gecko species, the Schlegel's Japanese gecko (Gekko japonicus) and the House gecko (Hemidactylus frenatus), have reported. In September 2021, new geckos were collected from buildings near the Incheon Port. To determine their identities, we evaluated 16 morphological parameters (7 size values and 9 scale count values) and analyzed the partial sequences of two mitochondrial DNA genes (CO1 and CytB) from 21 adult geckos. In addition, to evaluate the possibility as an invasive species, we constructed the haplotype network and Bayesian inference (BI) and Maximum likelihood (ML) phylogenetic trees, including 27 Chinese populations. Based on the values of the morphological parameters and the BLAST (Basic Local Alignment Search Tool) analysis of the CO1 gene sequence (688bp), we determined the geckos as the Peking gecko (G. swinhonis), an endemic species in China. In the results of the phylogenetic trees, the geckos in the Incheon population is intermixed with those from Chinese populations. Overall, we suggest that the Peking gecko population in Incheon Port might be an invasive species recently introduced from multiple locations of China. This work was supported, in part, by the Basic Science Research Program through the National Research Foundation of Korea funded by the Ministry of Education (2020R1I1A3051885).