In an era of rapid population ageing, “point-ofcare” will be a general trend. It is indispensable for a medical device to possess the characteristics of portability, easy handling and convenient result-reading. In this study, we combine the nucleic acid amplification method with precise processes to develop a miniature biosensor. The loop-mediated amplification method (LAMP) has been used to amplify DNA with high specificity and efficiency under isothermal condition (65ºC) within one hour. The microchip consisted of poly (dimethylsiloxane) (PDMS) and mutilayer thin-film structure has temperature control set and optical detection unit to create appropriate working environment for LAMP reaction. With the increasing of LAMP product, we can detect the reaction by-product sharply by surface plasmon resonance (SPR) and optical interference. Furthermore, we would like to take the partial gene of hepatitis B virus (HBV) as a detection target in our experiment. At present, we have accomplished the specificity and sensitivity test of LAMP reaction. The sensitivity of HBV LAMP reaction determined by agarose gel electrophoresis is 150 copies/tube. Therefore, we are going to develop a miniature isothermal amplification system with an integrated optical detection unit to provide a portable, label-free and real-time monitoring biochip.