The present invention belongs to the pharmaceutical field, and in particular, it relates to a pharmaceutical formulation of palbociclib and a preparation method thereof. The pharmaceutical formulation comprises palbociclib, an acidic auxiliary material, and optionally a hydrophilic high-molecular material, which has better solubility and in vitro dissolution property as compared with the conventional formulation and can be used for enhancing in vivo absorption and bioavailability of palbociclib.