A support structure for wind-driven power generators comprising: a tubular tower provided with a hollow inner space, said tubular tower including multiple superposed annular sections defining transverse joints between them, each annular section being formed by at least two wall pieces made of prefabricated concrete defining vertical joints between them, each wall piece having a circular arc- or polygonal arc-shaped horizontal section the length of which defines the width of the wall piece, a straight vertical section the length of which defines the height of the wall piece, two transverse joint faces of constant or variable thickness and two vertical joint faces of constant or variable thickness defining the thickness of the wall piece on the perimeter thereof; foundation defining a support plane for the tubular tower; upper fixing configurations connected to an uppermost annular section of the tubular tower and lower fixing configurations connected to the foundation; post-tensioning cables connecting the upper fixing configurations and lower fixing configurations compressing the superposed wall pieces with one another, said post-tensioning cables running along the hollow inner space of the tubular tower; wherein the vertical joints of successive annular sections do not coincide with one another; characterized in that: in the vertical joints, the vertical joint faces of two adjacent wall pieces of one and the same annular section are arranged facing one another and lack structural connectors between them for the transmission of structural strains, allowing an independent structural behavior of the mentioned wall pieces; wherein the height of the wall pieces is less than twice their width. a tubular tower provided with a hollow inner space, said tubular tower including multiple superposed annular sections defining transverse joints between them, each annular section being formed by at least two wall pieces made of prefabricated concrete defining vertical joints between them, each wall piece having a circular arc- or polygonal arc-shaped horizontal section the length of which defines the width of the wall piece, a straight vertical section the length of which defines the height of the wall piece, two transverse joint faces of constant or variable thickness and two vertical joint faces of constant or variable thickness defining the thickness of the wall piece on the perimeter thereof; foundation defining a support plane for the tubular tower; upper fixing configurations connected to an uppermost annular section of the tubular tower and lower fixing configurations connected to the foundation; post-tensioning cables connecting the upper fixing configurations and lower fixing configurations compressing the superposed wall pieces with one another, said post-tensioning cables running along the hollow inner space of the tubular tower; wherein the vertical joints of successive annular sections do not coincide with one another; characterized in that: in the vertical joints, the vertical joint faces of two adjacent wall pieces of one and the same annular section are arranged facing one another and lack structural connectors between them for the transmission of structural strains, allowing an independent structural behavior of the mentioned wall pieces; wherein the height of the wall pieces is less than twice their width. in the vertical joints, the vertical joint faces of two adjacent wall pieces of one and the same annular section are arranged facing one another and lack structural connectors between them for the transmission of structural strains, allowing an independent structural behavior of the mentioned wall pieces; wherein the height of the wall pieces is less than twice their width.