Protected man-made parks of Ukrainian Polissya, created in the period of postmodernism, are conservation oriented, historical, cognitive and educational objects. Landscape design is a synthesis of traditions and new transformation trends. On the territories of protected man-made parks, natural existence and distribution of rare species are maintained, endangered and vulnerable species are protected, hydrological functions are improved, and valuable landscapes are preserved. Concentrated in Rivne region, five parks, which have the status of complex natural monuments of local significance, were created in Ukrainian Polissya in the 1960s. According to the results of the analysis of formation and development history, the transformation of complex natural monuments (CNMs) of Ukrainian Polissya for a period of over 60 years is shown. CNMs have a simple planning structure of the following types: cross-shaped ("Vysotsky Arboretum"), star-shaped ("Bilsky Arboretum", "Sarny Arboretum"), loop-shaped ("Rokytne Arboretum"), and combined ("Tryputnyansky Park"). Of the three parks with regular planning, the biggest change can be observed in the complex natural monument "Bilsky Arboretum". This is due to the growth of hedges, which are not currently formed, and to the violation of the boundaries of meadows, where self-seeding plants appear. The dendroflora of five man-made parks is represented by 157 species, which belong to 19 orders, 32 families, and 81 genera, with 111 of them being included to the IUCN Red List. In two parks during their existence, there was an increase in the number of species by 11-50%, with the number of rare tree species amounting to 50-71%. In three parks under the influence of anthropogenic and ecological factors, there was a decrease in dendrodiversity, with 55-81% of species of woody plants remaining; аmong them 71-75% are rare tree species. Protected man-made areas of Ukrainian Polissya are valuable objects that need to be further developed and protected, whereas their collections of woody plants replenished and maintained.