Invasive plant species pose a significant challenge in urban ecosystems due to their ability to rapidly spread and adversely affect native plant communities. This study explores the ecological characteristics and distribution of invasive plant species in two prominent urban forests parks in Zagreb: Dubravkin Put and Kraljevec. The research aims to identify the invasive species present in these forests, analyze their ecological preferences and distribution patterns, and assess their impact on the local ecosystem. The research was conducted in two phases. The first phase involved field data collection on the presence of invasive species using GPS devices. The second phase involved analyzing ecological factors such as light, temperature, soil moisture, soil reaction (pH), soil nutrient content, and salinity using Ellenberg indicator values (EIV) to evaluate the habitat preferences of the identified plant species. A total of 17 invasive species have been inventoried, with 17 species recorded in the Kraljevec park-forest, while significantly fewer, only 9 species, were found in the Dubrakin put park-forest. These results indicate a high presence and spread of invasive species in both park-forests. Woody species such as Robinia pseudoacacia and Ailanthus altissima stand out particularly for their invasive potential. In Dubravkin Put, the analyzed ecological parameters showed a moderate preference for light (L= 6.78) and moderately warm conditions (T= 6.89). The average continentality value (K= 4.22) indicated suboceanic characteristics. Soil moisture (F= 5.11) was moderate, while soil reaction indicated acidity (R= 5.44). The soils were nutrient-poor (N= 4.22), and the species were intolerant to salinity (S= 0). The most common invasive species included Ailanthus altissima (Tree of Heaven), Reynoutria japonica (Japanese Knotweed), and Robinia pseudoacacia (Black Locust). In the Kraljevec park-forest, the ecological characteristics were similar. The plant species also exhibited a medium preference for light (L=7.33) and moderately warm areas (T= 6.73). The average value of continentality was (K= 4.27) with acidic soils (R= 3.37), low nutrient availability (N=2.60), and moderate soil moisture (F= 5.53). Invasive species like Acer negundo (box elder) and Ailanthus altissima (tree of heaven) were most prevalent in the northwestern parts of the forest. The results indicate a high presence and spread of invasive species in both urban forests parks. Woody species such as Robinia pseudoacacia and Ailanthus altissima particularly stand out due to their invasive potential. Maintaining the biodiversity and functionality of these urban forest ecosystems requires continuous monitoring and implementation of strategies to control invasive species. Comparing the ecological characteristics and distribution of invasive plants in Dubravkin Put and Kraljevec provides valuable insights for the future management of these urban forest areas.