The study on the hot spot stress distribution along the intersecting weld of circular hollow section（CHS） T-joints under in-plane bending moment was carried out. A finite element mesh model of CHS T-joints was established by radial tension method. A mesh density analysis and experimental comparison analysis were conducted on the reliability of the hot spot stress analysis results， and a basic density mesh that meets the calculation accuracy requirements was proposed. The distribution law of hot spot stress along the intersection line and the influence of geometric parameters were summarized through dimensionless geometric parameter analysis. The phenomenon of wave-crest-splitting at the crown point and three pattern of curve near wave crest were discovered during the splitting process. On this basis， by using a coefficient with a period π， a curve shape correction method and distribution curve parameter formula were proposed to correct the curve shape near the crown point. A statistical analysis compared with formulas and experimental data from two scholars at University College London（UCL） shows that the formula in this paper has a more concise expression and higher accuracy.