There are many morphological and histological studies in the world to investigate the structure of the external and internal organs of insects. These studies not only serve to illuminate the biology of insect species, but also to reveal taxonomic relationships. For this purpose, the detailed structure of the testis and accessory glands that are the main organs of the male reproductive system of Bolua turkiyae Ünal, 1999 (Orthoptera: Tettigoniidae) was searched with a light microscope, scanning electron microscope, and transmission electron microscope techniques in 2019-2020 in Gazi University, Prof. Dr. Zekiye Suludere Electron Microscope Center in this study. B. turkiyae is an endemic species distributed around Bolu province in Turkey. The reproductive system of male B. turkiyae is comprised of testis, vas deferens, and accessory glands. When the cross-sections of the oval and yellow testis were examined, it was observed that they contain many follicles. There are cysts in these follicles that have the developmental stages of the sperm. From the distal ends of the follicles to the proximal ends, the germarium, growth zone, maturation zone, and transformation zone are located respectively. In these stages, spermatogonium, spermatocyte, spermatids, and finally spermatozoa are formed. Accessory glands are hollow tubular structures of two different sizes and diameters. Single-layered cubic or pyramidal cells surround the lumen in both groups of accessory glands. It is hoped that these new data will contribute to our understanding of the structure of the male reproductive system of B. turkiyae.