The formulation of effervescent tablets loaded with micronized powder of Caulis Dendrobii officinalis was optimized by single factor experiment and Box-Behnken design combined with response surface methodology with the qualities of the damp mass, granules and tablets as indexes. The optimal formulation was as follows: micronized powder of Caulis Dendrobii officinalis 44.5％, anhydrous glucose 25％, sodium bicarbonate 15％, citric acid 15％ and magnesium stearate 0.5％. The granules were prepared after adding 95％ ethanol containing 7％ polyvidone (PVP) K30 as adhesive and dried until the moisture content was below 3％. The final product could dissolve in 2.1 min, and the pH value of the solution was 6.2.