The invention provides an auxiliary strain gauge adhering device, and belongs to the technical field of component testing. The auxiliary strain gauge adhering device comprises an upper isolation film,an adhesive layer, thin film scale bars, a lower isolation film, and a strain gauge, and is characterized in that the upper isolation film is located at the outermost layer and is adhered and fixed to the adhesive layer; the lower isolation film is located at the bottom layer and is also adhered and fixed to the adhesive layer; the upper isolation film is a monolithic isolation film; the lower isolation film is a small grid-shaped isolation film; the adhesive layer is sandwiched between the upper isolation film and the lower isolation film; and the upper isolation film and the lower isolationfilm can be peeled off. The thin film scale bars with scales are arranged at the two sides of the adhesive layer; and the thin film scale bars are transparent thin film and have no adhesive. The backof the strain gauge is adhered and fixed to the adhesive layer by peeling off the lower small grid-shaped isolation film. The adhesive layer, the upper isolation film and the lower isolation film areall flexible materials. The auxiliary strain gauge adhering device is used for the testing of component strain or deformation.