This invention belongs to the field of the silica micro-machine and the electrical chemistry, specific about a kind of micro sensor on the base of antibody and antigen method to detect the fibration of the liver. It is made up of the working electrode, reference electrode, pairing electrode and the base board. Among these, the working poles have the shape of circle or like a circle and they range symmetrically. And the reference electrode is like the letter 'U', set between the working electrode. Besides, the pair pole looks like a trip, set between the reference poles. The base board is made up of the composite silicon packing block and the SiO2 layer. There are 4-8 working electrode and the electrode and the SiO2 layer are bonded with the Ti tack coat, and each electrode can be made with the simple film technology of the IC technology. In a word, the invention has small micro-sensors, costs little and has high authenticity. It can detect out the concentration of the antigen in the serum quantitatively and meanwhile measure several data of the serum, and the quantity of the serum is small.