The berry bug, Dolycoris baccarum is cause significant damage when its populations are high. Although know mainly as a cereal pest, it is polyphagous, attacking a variety of crops in Turkey and Palearctic region (Lodos, 1986; Panizzi et al., 2000). D. baccarum is economically important insect, so, in order to combat with D. baccarum need to well-know the structure of the reproductive system of this insect. Therefore, the purpose of this study is to describe the morphological and histological structure of the male reproductive system of D. baccarum and contribute to the knowledge of the male reproductive biology of Pentatomidae.