Excavations were carried out between 2003-2020 in the Hadrianoupolis from the Paphlagonia Region six buildings dated to the Late Antiquity and floor mosaics were found that reflect the period's decoration characteristics. High quality workmanship floor mosaics were found on the apse and bema floors of the building, in which excavation is still ongoing, and which can be named as the Northwest Necropolis Church due to its location in the city, which is mostly referred to as Northwest Necropolis Church in publications. The floor of the church, which has two different construction phases, was decorated with mosaics in different techniques and styles in both periods. The mosaics, some of which were destroyed during illegal excavations and road construction works in the past, and completely unearthed in 2017-2018 excavations, reflect the 4-6th AD century Byzantine mosaic art style. In the mosaics decorated with geometric, floral and figurative patterns seen on almost every floor mosaic of the period; an inscription containing information about the constructor was found. The mosaics, which were strengthened under the supervision of restoraiors and conservators, were preserved in accordance with appropriate techniques. In this study, the mosaics adorning the apse and bema floors of the church were compared and evaluated with similar examples in the region and different geographies and explained in detail.