Abstract: In order to improve the precision of the core design calculation code, an advanced pin power reconstruction method was introduced in this paper. The new method used transverse integral flux distribution as the constrained function and obtained the 17 development coefficients by applying weight coefficient method. Comparisons between the new method and the traditional 13 and 21 development coefficients methods were carried out based on the B&W and IAEA2D benchmarks. The comparison results show that the new method gives better calculation accuracy than the traditional 13 development coefficients method. Moreover, the new method is more consistent to the 21 development coefficients method.