The species Halyomorpha halys (Stål), which is endemic in East Asia, was first detected in North America in 1996 and was probably introduced into Europe in 2008. The species is polyphagous. It consumes over 170 host plant species and significantly impacts crop production. In Greece the first recording of its presence was in 2014, when it was reported as a nuisance in houses in the region of Athens. The present study describes the systematic spread and damage of this invasive pest, including the first recorded identification in peach and olive cultivations in the prefecture of Imathia in central Macedonia, Greece. Sampling was carried out in representative peach and olive farms during July and August, 2018 and 2019 in which significant levels of fruit damage were recorded, especially during 2018. The population of the species was recorded throughout the winter seasons of 2018 and 2019 in which overwintering adults were systematically recorded in shelters and other constructions near fruit orchards. Given the dynamics of the species and its destructive impact on a wide range of host species, H. halys is expected to be a major pest. Additionally, considering that the prefecture of Imathia is the most important peach growing area of Greece, further studies of the presence and population dynamics of this species along with the establishment of particular management actions to control the population is imperative for the future protection of horticultural production in Greece.