Biosensors that are based on nucleic acids as recognition elements or as target analytes are called nucleic acid-based biosensors (NABs). NABs mainly use deoxyribonucleic acid (DNA), ribonucleic acid (RNA), aptamers (both DNA and RNA), and peptide nucleic acid (PNA) as oligonucleotide probes. Different methodologies can be used to construct a variety of NABs, including electrochemical, optical, and mass-sensitive biosensors. Over the last few decades, nucleic acid-based analysis has gained much interest for various detection and monitoring food safety applications. Nucleic acid-based biosensors (NABs) are preferred over other sensor types due to their high sensitivity and selectivity. Moreover, among nucleic acids, aptamers represent new, promising recognition elements for biosensor development.