A ticket detection system comprises magnetic induction unit for obtaining soft / hard magnetic signal, soft / hard magnetic signal processing circuit for amplifying and filtering said signal and for converting said signal to be digital signal, judgment circuit for converting digital signal to be soft / hard magnetic image and for comparing said magnetic image with standard ticket model to identify true or false of ticket. The said magnetic induction unit consists of magnetic transducer with a magnetic head being exerted with external magnetic field and with another magnetic head free of external magnetic field.