The use of cold-formed steel currently develops very fast. It is due to its advantages such as durability, stability, non-combustibility, sustainability, and cost-effectively. On the other hand, its disadvantages are difficult to connect, low fire resistance, residual stress on the cross-section that affects buckling resistance. In the previous research, to overcome the lack of buckling resistance in cold-formed steel, the composite connection is proposed. A recent study about cold-formed steel connection is divided into non-composite and composite research. The result of composite research has a higher moment capacity than non-composite. Most of the composite research is focused on beam and column with the concrete slab above the beam. In the current study, a T-shaped of gusset plates is used as a joint connector. This study aims to investigate the effect of the bottom flange cleat on the joint capacity. The slab panel's material is a Lipped Channel Section with the size of 12524 as the frames and reinforcements. The grade of cold-formed steel is fy = 530 MPa and fu = 590 MPa, while the T-shaped plate connector's strength is S355. The bolt used has a diameter of 10 mm, fy = 800 MPa. The flange cleats used is L100×100×10×80. The parametric study was conducted based on Eurocode 3. The connection with the additional bottom flange cleat has a higher moment resistance than without the flange cleat. The additional bottom cleat's influence is that the moment resistance increased the moment resistance from 17.11 kNm to 23.32 kNm. The predicted failure mode of the connection could be the failure that occurred at the top side of the cold-formed section of the slab due to the bending.