PURPOSE: A urease inhibitor containing Oenothera odorata JACQ. extract and sea weed extract is provided to enhance the inhibition effect.CONSTITUTION: A urease inhibitor contains Oenothera odorata JACQ. extract and sea weed extract containing fucoidan as an active ingredient. The sea weed includes Laminaria japonica Areshoung or Undaria pinnatifida Harvey Suringar. The sea weed extract contains 0.5-3 parts by weight based on 1 part by weight of the Oenothera odorata JACQ. extract. The Oenothera odorata JACQ. extract is prepared using water, methanol, ethanol, isopropyl alcohol, acetone, 1,3-butylene glycol, ethylene glycol, propylene glycol, glycerin, or ethyl acetate from Oenothera laciniata, Oenothera striata, Oenothera biennis, or Oenothera erythrosepala. The Oenothera odorata JACQ. extract contains a large amount of ellagic acid, pentagalloyl glucose, gallic acid, catechin, procyanidins, and proanthocyanidin.COPYRIGHT KIPO 2012본 발명은 우레아제 저해제에 관한 것으로서, 보다 뛰어난 저해 활성을 갖는 우레아제 저해제를 제공하는 것을 목적으로 한다.본 발명은 달맞이꽃 추출물과 후코이단을 함유하는 해조추출물을 유효성분으로 하는 우레아제 저해제를 개시한다.상기 해조는 다시마 또는 미역인 것을 특징으로 한다.