The invention provides an
embolism microsphere capable of slowly releasing drugs and controlling degradation speed and a preparation method thereof, the method comprises the following steps: dissolving a dispersant in an
oil phase liquid, and stirring at a first preset temperature to obtain a dispersion liquid; dissolving
gelatin in water at a second preset temperature to obtain a
gelatin solution; the preparation method comprises the following steps: dissolving a compound with negative
electricity groups in water, and adding alkali liquor and an initiator in an ice bath to obtain a modified solution; adding the modified solution into a
gelatin solution, stirring to obtain a water-phase pre-polymerized solution, dropwise adding the water-phase pre-polymerized solution into the dispersion solution, premixing, adding a cross-linking agent and a catalyst, and directly
grafting negative
electricity groups onto gelatin molecules in a low-temperature free
radical polymerization manner to obtain an
intermediate product; and performing post-treatment to obtain the
embolism microspheres. According to the preparation method disclosed by the invention, a non-degradable material is not needed, negative
electricity groups can be directly grafted on the surface of gelatin, so that the
embolism microspheres have efficient
drug loading performance and good long-period
drug sustained release, and the degradation speed of the embolism microspheres is controlled.