The utility model discloses a connecting structure of transformer low-voltage leads. The connecting structure comprises a coil outlet end and a connecting piece, wherein the coil outlet end and the connecting piece are mutually lapped. The connecting structure further comprises two soft copper bars which are uniform in size. The soft copper bars are clamped from the front face and the rear face of the lapped position of the coil outlet end and the connecting piece respectively. The plane size of the soft copper bars is larger than that of the lapped position of the coil outlet end and the connecting piece. Bolt holes are formed in the planes of the two ends of the part, beyond the lapped position of the coil outlet end and the connecting piece, of each soft copper bar. The two soft copper bars are screwed into the bolt holes through bolts and then locked through nuts. The locked soft copper bars are provided with a hollow insulation box in a clamped mode, and the surfaces of the peripheries of the soft copper bars are wrapped with the insulation box. The connecting structure has the advantages of being simple, convenient to operate, easy and convenient to manufacture and high in generality, the soldering operation process is omitted, and labor efficiency can be improved substantially; moreover, pseudo soldering is avoided; meanwhile, connection is firm and reliable, the insulation performance of the peripheries is excellent, and electrical performance of a transformer can be ensured.