This paper presents an alternative design procedure for lateral-torsional buckling of cantilever I-beams which aims to simplify the calculation of critical loads and design moments. In the first part of the study, a closed-form equation is proposed to determine elastic critical lateral-torsional buckling load. The accuracy of the equation is validated through ABAQUS which is a software suite for finite element analysis. The second part includes bending tests conducted on European IPE100 section cantilevers. The purpose of the experiments is to determine the failure modes and loads in order to obtain baseline data for the design curve and comparison with analytical results. Finally, a design procedure is presented for cantilever I-beams which considers elastic buckling, inelastic buckling and full plastic strength. Design moments calculated by the presented design procedure, Eurocode 3-2005 and AISC360-10 are compared. It is found that the design moments obtained by the presented design procedure are in good agreement with those obtained by the procedures introduced in mentioned codes. (C) 2015 Elsevier Ltd. All rights reserved.