This study presents a new concept for a deck plate and an accompanying application for a slab system that is easy to fix and separate during construction, while ensuring safe construction loads and optimal flexural performance. Finite element analysis (FEA) was used to determine the load on the fixing device’s contact surface and the specimen’s shape. A direct tensile test was then performed using a universal testing machine to evaluate the anchorage performance of the fixing device. The results of this test were used to optimize the details of the fixing device, which were then evaluated for safety against construction loads. The installation interval and method of the fixing device were varied to determine the maximum installation interval, which was within 300 mm. Finally, flexural performance was evaluated based on the details and spacing of the fixing device installation. The results showed that the details and spacing of the fixing device did not have a significant effect on flexural performance, provided that safety against construction loads was secured. This study describes a promising solution for a slab system that is easy to install and separate during construction, while ensuring safety and flexural performance.