An ultralow expansion brake rubber hose comprising an inner rubber tube, a first reinforcing layer, a second reinforcing layer and an outer rubber layer, wherein a thermosetting resin which penetrates the reinforcing fibers constituting the first reinforcing layer and which is cured at vulcanizing temperatures is cured by vulcanization to turn the first reinforcing layer into a solid cured layer. By turning the first reinforcing layer into the solid cured layer, the mutual slippage between the reinforcing fibers of the first reinforcing layer can be prevented, and a brake rubber hose having low expansion and excellent durability can be obtained. The rubber hose can be produced by carrying out the continuous steps of braiding a first reinforcing layer around an inner rubber tube, immersing the first reinforcing layer in a thermosetting resin solution capable of penetrating the reinforcing fibers constituting the first reinforcing layer and having low viscosity to cause the thermosetting resin solution to penetrate the reinforcing fibers, braiding a second reinforcing layer, and extruding an outer rubber tube on the external surface of the second reinforcing layer.