This chapter provides an insight on different kinds of mycotoxins and methods to determine mycotoxins, with a particular focus on ochratoxin, patulin, aflatoxins, fumonisins, trichothecene, zearalenone and citrinin. Several analytical approaches for the determination of mycotoxins are summarized. The traditional methods such as immunochemical and chromatographic procedures, and some new methods, such as biosensors and optoelectronics devices used to scale down the equipment in a portable way are explained.