Concrete composite slabs, as an important component of prefabricated structures, are widely used in practical engineering. The connection forms between prefabricated slabs have a significant impact on the load-bearing performance of composite slabs. The reinforced concrete composite slab without external rebars enhances the load transfer performance between closely spaced slabs without external rebars through methods such as grooving, bending longitudinal rebars for load transfer, and bonding carbon fiber composites at the bottom of joints, showing great practical value. This paper elaborates the research progress of scholars in recent years on reinforced concrete composite slabs without external rebars, and based on experimental studies, compares and analyzes the effects and mechanisms of various reinforcement measures on the load-bearing capacity of composite slabs without external rebars. It also analyzes the impact of changes in factors such as groove forms at slab edges, types of rebars at joints, and the use of fiber composites on the load-bearing capacity of composite slabs. The research indicates that with appropriate connection forms and reinforcement measures, the failure mode of composite slabs exhibits characteristics of “two-way slabs”, with load-bearing capacities exceeding 90% of cast-in-place slabs, approaching the level of “equivalent cast-in-place”.