The maize spotted stem borer Chilo partellus Swinhoe 1885 (Lepidoptera: Crambidae) was recorded for the first time in Turkey in 2014. This pest is described as invasive, especially in the current climate change dispensation. It is important to investigate the population dynamics of C. partellus for better management practices. We studied the species abundance distribution (SAD) models and some biodiversity indices of three major stem bores, C. partellus, Ostrinia nubilalis and Sesamia nonagrioides as these are the most common and major stem borers of maize in the Mediterranean Region. With the help of light traps, weekly catches of the three major maize stem borers were collected during two maize growing seasons (first cropping and second cropping seasons) in 2018 and 2019. The results showed that C. partellus emerged earlier (April-May) and was very dominant throughout the first cropping season of maize. Ostrinia nubilalis and S. nonagrioides emerged late in June-July, and its population remained low throughout the first cropping season. The population structure of all three stem borers was similar throughout the second cropping season of maize. The relative abundance (RA) of C. partellus was significantly higher than that of O. nubilalis and S. nonagrioides in the first cropping (p <.0001) when compared to the second cropping season (p >.05) for both years. In the first cropping season for both years, no SAD model fitted the observed species distribution, although Fisher's log series was relatively similar. In the second cropping for both years, the geometric series distribution model fitted the observed SAD. The Berger-Parker dominance index was greater for the first cropping season than that of the second, whereas the opposite was true for the Simpson's evenness and evenness of Pielou. High RA of C. partellus and the geometric series distribution observed in the second cropping are indicative of a possible dominant status of the C. partellus in the Mediterranean Region of Turkey. Our findings indicated that seasonality is a fundamental driving factor influencing the distribution of the three major stem borers of maize in the Mediterranean Region. In addition, the long and warmer winters could be the reason for the dominance of C. partellus as indicated by the diversity indices.