The invention discloses a strain gage pasting device which is used for pasting a strain gage to a to-be-pasted area. The strain gage pasting device comprises a positioning plate, a compression mechanism and a sucking disc assembly, wherein a strain gage positioning groove and a strain gage line guiding groove are formed in the front end of the positioning plate, and a through hole is formed in the positioning plate and communicated with the strain gage positioning groove; the compression mechanism comprises a pressing plate, a pressing block and a guide column, the guide column is connected to the back end of the positioning plate, the pressing plate is connected to the guide column in a sliding manner, the pressing block is connected to the through hole in a sliding manner, and the back end of the pressing block is connected with the pressing plate; the back end of the pressing block does not exceed the strain gage positioning groove, and a containing hole is formed inside the pressing block; and the sucking disc assembly comprises a vacuum sucking disc, a connecting pipe and a connecting joint, the vacuum sucking disc is fixed to the front end of the containing hole, the connecting joint is fixed to the back end of the containing hole, and a connecting pipe is used for connecting the vacuum sucking disc with the connecting joint and located in the containing hole. By means of the pasting device, the strain gage can be sucked to be accurately pasted into the to-be-pasted area.