The invention discloses a nifedipine sustained release tablet and a preparation method thereof. The grain diameter D90 of nifedipine is 5-10 mu m, and a tablet core is prepared from, in percentage byweight, 25% of nifedipine, 5%-10% of retardant composition, 0.5%-1.5% of tween 80 and the balance of other auxiliary materials. In order to guarantee the storage quality of the tablet core, the tabletis colored and coated, and the weight gain of a coat is 4%-5%. Initiative formula composition is adopted, a sustained release mode is innovated, and the nifedipine sustained release tablet capable ofcontinuously releasing a drug within 12 h is prepared, two times of human body pre-BE (bioequivalence) (12 cases, empty stomach/full stomach) research prove the BE of the product, and besides, a dissolution method related in vitro and in vivo is developed. The drug release principle and process monopoly of the nifedipine sustained release tablet are broken through, the adopted formula and preparation process are simpler and more controllable, facilitate industrial production in China and provide more clinic choices for patients and doctors, and the medication burden of the patients is reduced.