The invention discloses an integral construction method for heat preservation and decoration of an outer wall, relating to the technical field of constructional engineering, in particular to a construction method for external heat insulation of an outer wall. The construction method comprises the following steps of: processing base level, dividing mesh and playing a line, cutting plate, mounting a bottom bracket, mounting a postposition bearing bracket, sticking plate materials, reinforcing mechanical fixing components, caulking, dividing joint to do waterproof sealing and coloring, repairing dividing-joints and repairing a whole body. The invention solves the difficult problems of hollowness, cracking, dropping, soaking and the like of architectural coating, and synchronously achieves the architectural effects of heat preservation, heat insulation, water resistance, decoration and the like.