This paper presents a numerical study on high strength steel endplate connections under fire conditions conducted using ABAQUS, to reveal more information and understanding on behaviour of high strength steel endplate connections under fire conditions. The validations of the numerical modelling against all representative experimental results conducted on moment–rotation relationship, failure mode and yield line pattern of connections show good agreements exist. It has been demonstrated that this finite element analysis gives reasonable accuracy compared with experimental results, providing an efficient, economical, and accurate tool to study the fire performance of high strength steel endplate connections. Hence this numerical analysis method can be used with confidence to predict the behaviour of high strength steel endplate connections up to the maximum moment under various fire conditions as well as at ambient temperature.