A series of experiments on Thin walled steel stiffened concrete composite (TWSSCC) beams is reported. The TWSSCC beams consist of cold-formed sheet as formwork during construction stage and as reinforcement during service stage and infill concrete. As the three sides of the beams were enclosed by cold formed sheet, it aided in confinement whereas at the top, the braces were provided at suitable spacing which provided partial confinement. Companion specimens of concrete cubes, cylinders and prisms were also tested for compressive strength and elastic modulus properties.  Specimens of cold formed sheet and reinforcing steel bars were tested in tension to ascertain their yield stress and modulus of elasticity. The beams were tested for pure bending and the results were used to to study the failure modes of the beams. Load, Moment, Flexural rigidity and Rotation at yield and ultimate stage were determined from experiments. Based on the observations during testing, the failure modes were classified into two different types which were the flexural compression failure mode and shear bond failure. The influence of spacing of braces and nature of bond on Ultimate Strength and Deflection were reported. It is confirmed that, closer spacing of braces in pure bending region did not show significant influence in the flexural strength. Hence, the braces at the spacing of least lateral dimension held good for confinement.