Ibuprofen is a non-steroidal anti-inflammatory drug which belongs to a group of derivatives of propionic acid. It has antipyretic and analgesic effects which have wide application in treating acute and chronic pain. It is extremely important to be able to determine ibuprofen in biological samples, because of diagnosing a possible overdose with a drug, or because of determining a suitable therapy because of possible interferences in contact with other active pharmaceutical substances. It is also really important to determine ibuprofen in drugs which are in the shape of tablets, syrups and creams. In that way, quality and validity of a drug are being ensured, and it is also determined whether it can be released on the market. The concentration of ibuprofen is being controlled regularly in waste water because of a possible discharge of untreated waste in the environment, usually coming from the pharmaceutical industry, hospitals and domestic waste waters, which is why the ibuprofen is considered to be a serious pollutant. The most common methods of determining ibuprofen are: high-performance liquid chromatography (HPLC), fluorescence spectroscopy or spectofluorimetry and voltammetry. When developing new methods, their accuracy is usually checked by comparing the results with the results obtained using another method, mostly HPLC.