_-L-Fucosidase (EC 3.2.1.51) (FUCA1) is a hydrolase that is able to cleave _-L-fucosyl moieties from glycoconjugates and oligosaccharides. Fucosidase plays pivotal roles in cell differentiation, apoptosis, inflammation and host-pathogen interaction. Furthermore, abnormal concentrations of this glycosidase have been observed in patients suffering from cancer, fucosidosis, rheumatoid arthritis, cystic fibrosis, and leukocyte adhesion deficiency. Industrial applications of _-L-Fucosidase (FUCA1) include synthesis of fucosylated analogs that could serve as antiadhesion compounds, cancer vaccines, and anti-inflammatory therapeutics. _-L-Fucosidase Assay Kit provides a simple, sensitive and high-throughput adaptable approach to detect physiological concentrations of this glycosidase in a variety of biological samples. In this assay, _-L-Fucosidase uses a synthetic chloro p-nitrophenol derivative (R-pNP) as an _-L-Fucosidase substrate and releases a chlorinated pNP derivative which can be measured kinetically under acidic conditions (OD 405 nm). The assay involves a one-step simple reaction, with minimal sample preparation and does not need a stop solution to complete the reaction. The assay can detect as low as 20 μU of _-L-Fucosidase activity in a variety of samples.