The invention discloses a small-aperture 16-component conical strain gauge comprising a strain head, a piston rod and a liquid storage cavity, wherein the upper end of the piston rod is provided witha positioning pin; the strain head comprises an aluminum cap, a glue hole, a strain gage, an adhesive groove, an adhesive retaining ring, a lead hole and a temporary fixing hole; the adhesive groove is arranged on the outer wall of the strain head, the strain gage is installed in the adhesive groove, the lead hole is arranged on the peripheral side of the strain head and communicates with the adhesive groove, the data line of the strain gage protrudes from the lead hole, the aluminum wire passes through a temporary fixing hole after the liquid storage cavity is filled with epoxy resin mixed glue such that the piston rod is connected to the strain head at the front end, the piston rod moves in the direction of the liquid storage cavity, and the mixed glue overflows from the glue outlet holeand adheres to the bottom of the hole. The small-aperture 16-component conical strain gauge provided by the invention can collect rock strain data in 16 different directions, and the ground stress measurement results are more accurate, the required diameter of the drilling hole is 60mm, the single-point installation cycle is shortened from the past 6h to 2h, the test efficiency is high, and three-dimensional ground stress can be measured with more reliable test results.