<p>In recent decades, with the increase in urbanization, investigations related to arthropod species groups living in cities have come to the fore. Species adapted to the urban environment occupy habitats that provide them with a favorable habitat, abundant food sources and better chances of survival. The heterogeneity and microclimatic conditions of the environment can greatly affect the quantity and species composition of mosquitoes in inhabited areas. In addition to examining the species assemblage, the aim of the surveys was also to examine the effect of the heterogeneous environment on the distribution of mosquitoes. Over the course of surveys conducted over four years at 12 sampling points in the inner area of Sopron, the presence of individuals of 26 species was detected. The results of our studies indicate that there are significant differences in the composition and quantity of mosquito assemblages from place to place and from year to year. In the first phase of the survey (2019–2020), the differences between the groups, as shown by the ordination, were decisive. In contrast, in the second phase (2021–2022), phenological differences played a decisive role. The significant amount of precipitation may have caused the difference between the two periods in the spring and early summer of 2019–2020. In the second period, both spring and summer were dry. In addition to landscape characteristics, microclimatic conditions and geographical location also play a role in the development of these differences. The sampling sites formed strongly distinct groups. However, these do not coincide in terms of phenological conditions and species composition. The results also indicate that the impact of landscape characteristics may vary depending on the geographical area. Our results can be applied from a public health perspective, as well as during the implementation of procedures aimed at reducing the level of harassment.</p>