Urease inhibitor is a kind of chemical preparation which can inhibit urease activity in soil and delay urea hydrolysis. Soil urease is the specific hydrolytic enzyme which can catalyze urea hydrolysis in soil. There are main two aspects about the mechanism of urease inhibitor to control urea hydrolysis. Firstly, the oxidation of SH decreases the activity of urease. Secondly, competing for ligand reduces the activity of urease. Hydroquinone is mainly used in China. At present, several kinds of special fertilizer containing hydroquinone, dicyandiamide and other slow-release nitrogen fertilizer have been widely used in a certain area. Urease inhibitor can also be used as feeding additives for ruminant animals, which can effectively reduce the ammonia content in the air in poultry houses, improve the environment status, and improve the animals' utilization efficiency of nitrogen.

The mechanism of action includes:

Urease inhibitors blocked the active position of soil urease on urea hydrolysis, thus reducing the activity of urease.

The urease inhibitor itself is also a kind of reducing agent, which can change the REDOX conditions of the micro-ecological environment in the soil and reduce the activity of soil urea.

As urease inhibitor, hydrophobic substances can reduce the water solubility of urea and slow down the hydrolysis rate of urea.

Anti-metabolic substance urease inhibitor can disrupt the metabolic pathways of microorganisms that produce urease, block the synthesis of urease, and reduce the density of urease distribution in soil, thus reducing the decomposition rate of urea.

Urease inhibitor itself is a kind of compound with similar physical properties as urea. In soil, urease inhibitor moves synchronously with urea molecules, protecting urea molecules from urease catalytic decomposition. When urea is used, a certain amount of urease inhibitors is applied, which limits the activity of urease and slows down the decomposition of urea, thus reducing the ineffective degradation of urea.