Palbociclib polycrystal form and preparation method thereof

The invention relates to a palbociclib polycrystal form and a preparation method thereof. In an X-ray powder diffraction pattern, characteristic peaks exist near the angles 2theta of 7.17 degrees, 7.62 degrees, 7.82 degrees, 8.49 degrees, 11.62 degrees, 11.81 degrees, 12.62 degrees, 22.96 degrees, 25.10 degrees and 25.63 degrees, wherein 2theta can have the deviation of +/- 0.2 degree; a differential scanning calorimetry analysis chart shows that an exothermic peak appears near the temperature of 207 DEG C. The preparation method of the crystal form C is easy to implement, a solvent is small in dosage and free of toxicity, the production cost is low, and the preparation method has obvious advantages in the aspect of industrialization; a substantial progress of the whole novel crystal form preparation process is achieved, and the process has significant progressiveness.