The invention discloses an oral solid preparation for treating hypertension and a preparation method thereof. The oral solid preparation for treating hypertension is composed of the following components: 12-26 parts of active ingredients of traditional Chinese medicine, 4-7 parts of mushroom polysaccharide, soybean peptide 3-5 parts, purple corn extract 2.2-3.5 parts, gallic acid 0.5-0.8 parts, citric acid 0.4-0.6 parts, taurine 0.3-0.5 parts, lutein 0.1-0.3 parts, lycopene 0.1-0.3 parts parts, 0.1-0.2 parts of genistein; the active ingredient of the traditional Chinese medicine is composed of the following components: 3-6 parts of betulin alcohol, 2-3 parts of Sanbai grass extract, 2-3 parts of mulberry leaf baking powder, red 1-3 parts of sea cucumber extract, 1-3 parts of Humulus japonicus extract, 1-3 parts of wax gourd extract, 1-3 parts of weed extract, 1-2 parts of creeper extract. The present invention can enhance immunity, relieve fatigue, invigorate the kidney, invigorate qi, activate blood, inhibit the rise of blood sugar and blood pressure, reduce the burden on the kidney, also have anti-oxidation, maintain vascular permeability and elasticity, effectively prevent and treat high blood pressure, and has a remarkable curative effect. And safe without side effects.