Abstract: Tapered members are widely used in portal lightweight steel structures in Europe and Australia. Currently, the study is rare on the stability of the tapered beam-columns with sinusoidal corrugated web. Based on the design formulas in CECS 102:2002, the design formulas used to calculate the in-plane and out-plane stability capacity of the tapered beam-columns with sinusoidal corrugated web were proposed, and they were verified by FEM numerical results. A test program of 2 tapered specimens was carried out and the observed results consisted well with FEM results, thereby the proposed formulas were confirmed to be used rationally.