The utility model discloses a steel longeron formula member reinforced structure of deriving. It includes upper chord, lower chord, erects web member and diagonal bracing, erects web member and diagonal bracing and all connects between upper chord and lower chord, erects node of web member, diagonal bracing and upper chord or lower chord sharing. This embodiment is still set up one and is derived the formula and connect the member on the steel longeron has had the member, connect member one end and be connected with the diagonal bracing, and the other end is continuous with the lower chord to the drift of reduction diagonal bracing, the stability and the bearing capacity of increase member. The utility model also provides a steel longeron is consolidated to the formula member of deriving that has above -mentioned structure.