Abstract: This paper preliminarily deals with the static strength of fillet welds and the related calculating formulae,based on the analysis of the test results of the stress and strain distribution in end fillet welds and the static tensile strength of fillet welds.It is found that the shape of fillet welds has a great influence on the stress and strain distribution.One can reduce the concentration of stress and strain and increase the static strength by increasing the leg length in the loading direction.Moreover,the safety factors of several traditional formulae for calculating the strength of fillet welds are evaluated,and a new simplified formula is proposed.