The concept of biochip is originated in 1980s, it can also be called micro-array technology. Biochip is a new and sophisticated technique developed by bio-science and micro-electronics. The birth of biochip technique is a great revolution in modern biology area. Nowadays, the biochip technique has been widely used in many fields, eg, spectrum analysis of gene expression, diagnosis of diseases, drug selection, tumor markers, detection of manifold kinds of viruses, etc. Based on its several characteristics such as high efficiency, sensitivity, economy, parallel, automation, gene-chip technique will be a novel modern diagnosis technique. In this article, the usages of biochip technique in preventive medicine fields including environmental health, virus detection, occupational hygiene, nutrition and food hygiene, were discussed.