The invention discloses a method for detecting fungaltoxin in an environment. The method comprises the following steps: marking an aptamer recognition probe by fluorescent dye, specifically bonding the aptamer with a to-be-detected fungaltoxin ligand so as to prepare a capture probe modified by nano-particles, and carrying out hybridization reaction by virtue of an un-reacted aptamer probe and the probe modified by magnetic nano-particles; carrying out magnetic separation, measuring the intensity of a fluorescence signal in supernatant, thus judging the amount of the fungaltoxin bonded with the aptamer; and carrying out unlinking, washing and magnetic separation on a magnetically separated hybrid, so as to realize the regeneration of a probe marked by the magnetic nano-particles. According to the method, the detection time in the whole detection process is short, the operation steps are simple and rapid, a large-sized instrument is not used in the specific reaction steps, so that the method is easy to popularize; and the resources can be repeatedly utilized and saved, and meanwhile, the step for preparing the capture probe is omitted, so that the detection is relatively rapid and simple, the detection limit is low, the specificity is good, and the method has very good practicability.