Abstract: A method for the treatment of fissures in concrete structures by means of repairing them with microcement-based material, comprising a method wherein the fissures, both horizontal and vertical or inclined fissures, are identified and analyzed. The treatment of the mentioned horizontal fissures comprises cleaning them and drying their surface using compressed air and subsequently filling them by means of gravity, the grout being poured with the help of a “pset”. The vertical or inclined fissures are treated by demarcating the sites for drilling and inserting the injector nozzles that permit cleaning and saturating the fissures with water, followed by the injection of the microcement grout under pressure. (FIG.