The invention relates to a
linagliptin and
metformin sustained-release composition and a preparation method thereof, and relates to the technical field of pharmaceutical preparations, the
linagliptin and
metformin sustained-release composition comprises a
metformin sustained-release tablet core and a
linagliptin coating layer wrapping the metformin sustained-release tablet core; the linagliptin
coating layer accounts for 2-3% of the total
mass of the composition; the metformin sustained-release tablet core comprises a plain pellet core, a
coating layer and a filling agent; wherein the plain pellet core comprises a large-particle-size pellet core of 1.10-1.25 mm, a medium-particle-size pellet core of 0.80-0.95 mm and a small-particle-size pellet core of 0.50-0.65 mm, and the
mass ratio of the large-particle-size pellet core to the medium-particle-size pellet core to the small-particle-size pellet core is 15: 60: 25; through particle size grading, pore differentiation design and hydrophobic modification treatment, the
drug release curve is optimized, the release uniformity is improved, and meanwhile, the production stability and the consistency of the preparation are improved.