The introduction of thin-walled stainless steel in buildings has been increased gradually for ensuring the sustainability thanks to excellent corrosion resistance and durability. Many studies on structural behaviors of stainless steel bolted connection fabricated with plane plate have been carried out. This paper is aimed at investigating the ultimate behaviors such as ultimate strength, fracture mode and out of plane deformation(i.e. curling) of channel bolted connection of cold-formed austenitic stainless steel with four bolts (2×2 bolt arrangement). End distance parallel to the direction of applied force is adopted as main variables. Specimens are planned with block shear fracture in ultimate state. In case of bolted connections with a long end distance, curling has also been observed. Ultimate strengths by test results are compared with those of current ASCE design specification and the influence of curling on ultimate strength is discussed.