Biosensors because of their specificity, fast response, low cost, play an important role in the food safety areas. This paper is presented as an overview of applications of electrochemical, optical, piezoelectric and calorimetric biosensors. The review includes detection of pathogens, antibiotics, biotoxins and pesticide residues. Factors limiting the practical application of biosensors to analytical problems are also presented. This report assesses future directions for biosensor development and the following future trends are suggested: more sensitive detection, increased integration and miniaturization, multianalyte analysis, more robust reagents and devices, and increased functionality of surface treatments. The technique offers great potential to meet the need for rapid and specific real-time detection of food contaminations.