Over the past few decades, the use of steel-concrete composite sections has increased globally, to take advantage of compression strength in concrete and tensile strength in steel, ensuring its connection by employing stress transfer elements denominated shear connectors.The main connection systems, endorsed by the current design codes, are used by applying welding as a fastening mechanism to fix connectors and any alternative system must be validated through an experimental program.However, this thermal procedure produces a concentration of residual stresses during the cooling process and the risk of perforation in Cold-Formed Steel sections (CFS), affecting the behavior efficiency of the composite sections.In this research, self-drilling screws are proposed as an alternative mechanical system for connectors fastening.The system efficiency was initially compared to the powder-actuated nails mechanism, validating their advantages of installation and structural behavior.An experimental program was carried out to validate the capacity and performance of the system, through screw shear tests and full-scale beam tests.Therefore, it was possible to characterize the local behavior in the fastening mechanism and the overall behavior in the composite system.According to results, self-drilling screws are a viable alternative to use as a fastening mechanism in shear connectors for CFS and concrete composite sections.The composite system developed full capacity, even in inelastic range, without disconnection between materials.Self-drilling screws remained fixed on steel shapes without mechanical damage, allowing greater deformations than displacements under service conditions.