The invention discloses a preparation method of andrographis paniculata capsules. Firstly, andrographis paniculata is prepared into andrographis paniculata dry extract powder, and then 10-11 parts of the andrographis paniculata dry extract powder and 14-15 parts of starch are taken according to part by weight so as to prepare the andrographis paniculata capsule as follows: firstly, mixing the andrographis paniculata dry extract and the starch in a mixer for 15 minutes, adding purified water accounting for 3% of the total weight into the mixture to be mixed for 15 minutes so as to prepare softmaterial; secondly, adding the soft material obtained from the step one into a hopper of a granulator, and utilizing a sieve with 20meshes for pelletizing; thirdly, drying wet particles under the temperature of 80 DEG C, and cooling the wet particles to the room temperature; fourthly, sieving the dried particles by a sieve with 18meshes for combining and mixing for 15 minutes, thereby obtaining an intermediate of the andrographis paniculata capsule; and fifthly, conducting capsule filling and polishing on the intermediate of the andrographis paniculata capsule, thereby obtaining the andrographis paniculata capsule. The andrographis paniculata capsule is scientific in formula, advanced in method, and obvious in medical treatment by the proving of clinical use.