The invention relates to the construction, in particular to the construction of steel lattice towers, intended for disposition of manufacturing equipment for various purposes.The lattice tower with increased bearing capacity is made with a rectangular cross section and comprises a body (1), consisting of interconnected sections (2), the faces of which comprise horizontal elements (3) and vertically oriented elements (4), forming a lattice. In the joint zone of sections (2) are mounted blocks (5), through which are passed prestressed cables (6).The process for increasing the bearing capacity of the lattice tower consists in that on the tops of the upper section of the exploited tower body are fixed cables, at the same time in the joint zone of sections of the body, on their ribs, are installed blocks, through which on diagonals of the sections, from the upper to the lower part of the body, are passed the cables and is performed the uniform pretension thereof, afterwards the cables are secured in the blocks.