DNA microarray technology is a new and powerful tool that allows the simultaneous analysis of a large number of nucleic acid hybridization experiments in a rapid and efficient fashion. The development of the DNA microarray chip has been driven by modern techniques of microelectronic fabrication, miniaturization and integration to produce what is referred to as “laboratory-on-chip” devices. The application of DNA chip technology includes the comprehensive analysis of multiple gene mutations and expressed sequences with regard to newer drug designs, host–pathogen interactions and the design of new vaccines. An advantage of microarray technology is that it can assist researchers to better define and understand the expression profile of a given genotype associated with disease, adverse effects from exposure to certain stimuli, or the ability to understand or predict immune responses to specific antigens. This paper briefly reviews DNA microarray technology and its implications with special reference to vaccine design. The technical aspects comprising array manufacturing and design, array hybridization, formatting, scanning and data handling are also briefly discussed.